丙泊酚对HEK-293细胞中表达的hERG钾通道及其无义突变体Q738X的抑制作用
|
摘要
长QT综合症(long QT syndrome,LQTS)可分为先天遗传性和后天获得性LQTS二类。先天性LQTS是由于编码心肌细胞离子通道的基因突变导致相应离子通道蛋白功能发生异常所致。目前已知的先天性LQTS的相关基因至少有十种,分别为LQT1-LQT10。其中LQT2是由于编码快速激活的延迟整流钾通道(rapid activating delayed rectifier K+ channel,IKr)的hERG基因(human ether-a-go-go-related gene,hERG)发生突变所致,IKr通道是形成心肌细胞动作电位复极3期的主要离子通道,对维持和决定动作电位时程的长短具有重要意义。最近报道在一日本遗传性LQTS家系中发现了hERG基因的一个新的突变位点Q738X,对该基因突变导致hERG钾通道功能的改变迄今国内外尚未见报道。
获得性LQTS主要是由于药物引起,药物主要通过两种机制作用于hERG钾通道：①直接抑制hERG钾通道,药物多与hERG钾通道S6区域的两个芳香族氨基酸Y652和F656具有高的亲和力,引起心肌细胞复极3期K+外流减少；②影响hERG蛋白的运输过程,造成细胞膜表面的hERG蛋白数量减少。
丙泊酚(propofol)又名异丙酚,是一种快速强效的全身麻醉剂,由丙泊酚引起的心电图QT间期延长,导致发作性晕厥、心脏猝死的心律失常事件时有发生。关于丙泊酚对QT间期影响的报道结果不一,一些研究认为丙泊酚能延长QT间期,相反,有些报道认为丙泊酚不影响甚至缩短QT间期。然而,在这些报道中丙泊酚常和其它药物同时使用,很难判定是丙泊酚单独作用的结果。我们假设丙泊酚对QT间期的影响及其机制可能与hERG钾通道的抑制有关。因此,本实验目的：①突变体Q738X-hERG的功能鉴定；②探讨丙泊酚对野生型(wide type, WT) hERG钾通道和共转染型WT/Q738X-hERG钾通道的影响；③丙泊酚对hERG钾通道作用机制的探讨,为临床合理化和个体化用药提供理论依据。方法
1.PCR定点突变Q738X、Y652A和F656C-hERG:采用PCR定点突变技术进行Q738X,Y652A和F656C突变,经DNA测序验证突变成功。
2.细胞培养和瞬时转染：人胚肾上皮细胞(human embryonic kidney cell line,HEK-293细胞)在含10%胎牛血清的高糖DMEM培养基中培养。采用磷酸钙沉淀或脂质体介导的方法进行瞬时转染。根据实验要求,转染质粒包括：①野生型WT-hERG;②突变型Q738X、Y652A和F656C-hERG;③共转染型：WT/Q738X-hERG;④对照组WT-hERG和空白质粒PBI。
3.全细胞膜片钳记录hERG钾通道电流：寻找表达有绿色荧光的单个HEK-293细胞,采用全细胞膜片钳技术,选用不同的实验方案,分别记录野生型WT、突变型Q738X、共转染型WT/Q738X和对照组的hERG钾通道电流和其动力学特征变化,以及丙泊酚对野生型WT、突变型Y652A和F656C和共转染型WT/Q738X-hERG钾通道电流和其动力学特征的变化。
4.Western blot检测hERG蛋白的表达：酶解收集蛋白,BCA法测蛋白含量,RIPA裂解蛋白,10%的SDS-PAGE凝胶电泳,PVDF转膜,5%脱脂牛奶室温封闭,抗hERG抗体(1：200),4℃孵育过夜,HRP标记的二抗(1：10000),室温孵育1 h,ECL显色。通过Quantity one软件分析每条带的灰密度值,与自身内参β-actin条带的灰密度相比,对每条带进行半定量分析。
5.双重细胞免疫荧光：分别观察转染WT、Q738X和WT/Q738X-hERG的HEK-293细胞上hERG蛋白的定位情况以及丙泊酚对WT-hERG蛋白定位的影响,转染36～48 h后4%多聚甲醛固定细胞,0.1%Triton X-100透化,2%牛血清白蛋白封闭,随后加入兔源抗hERG蛋白抗体和鸡源抗肌钙网蛋白抗体,4℃孵育过夜,次日加入FITC标记的山羊抗兔IgG和Alexa fluor 633标记的山羊抗鸡IgG的二抗,封片剂封片。
6.激光共聚焦技术
将细胞免疫荧光染色的HEK-293细胞进行激光共聚焦定位,FITC(绿色)和Alexa fluor(红色)分别用波长488 nm的氩离子激光和633 nm的氦氖离子激光激发。
7.统计学处理
所有数值用mean±S.E.M表示,使用pulse 8.67软件记录和分析通道电流,采用SPSS13.0和Origin6.0软件来拟合曲线和制图,加药前后采用配对t检验,组间比较采用单因素方差分析。P<0.05为差异有显著性。
1.突变体Q738X-hERG的功能鉴定
1.1突变体Q738X-hERG电流的记录
将转染有野生型WT-hERG的HEK-293细胞进行电生理记录,显示出典型的hERG钾电流,由时间依赖性电流和尾电流两部分组成。而在单独表达有突变型Q738X-hERG的HEK-293细胞中记录不到电流。将WT-hERG和Q738X-hERG(各2μg)共转染到HEK-293细胞中时,虽可记录到hERG钾电流,其电流图形也与WT-hERG电流相似,但其电流幅度明显低于WT-hERG (4μg)而与WT-hERG (2μg)电流大小相似。WT-hERG (4μg)、WT-hERG (2μg)和WT/Q738X(各2μg)的尾电流幅度依次为59.94±3.0、32.2±1.7(P<0.05vs 4μg WT-hERG)和26.2±3.5 pA/pF(P<0.05 vs 4μg WT-hERG);通过对WT/Q738X的动力学观察,发现Q738X突变不改变hERG钾通道的动力学特征(包括激活、失活和去活过程)。
1.2突变体Q738X的运输障碍
Western blot结果显示转染野生型WT-hERG的HEK-293细胞中可以检测到二条蛋白质条带(135和155 KDa),而突变体Q738X-hERG只出现135 KDa一个条带,共转染型WT/Q738X-hERG虽出现135和155 KDa二条蛋白质条带,但其155KDa的条带较弱。通过Quantity one软件分析每条带的灰密度值,对每条带进行半定量分析。结果显示,共转染WT/Q738X-hERG虽有成熟的hERG蛋白(155 KDa)的形成,但是表达量少于WT-hERG(P<0.01)。说明Q738X的突变影响hERG蛋白的运输,使其到达细胞膜表面有功能的hERG蛋白数量减少。
双重细胞免疫荧光染色后经激光共聚焦定位显示：转染有WT-hERG的HEK-293细胞,其绿色荧光主要分布在细胞膜上,与ER marker(红光)共定位后,虽有部分重叠,但膜上的绿色荧光仍然很清楚；而转染有突变体Q738X-hERG的HEK-293细胞,其绿色荧光主要分布在胞浆中,与ER marker共定位后,完全重合,说明突变体Q738X-hERG蛋白分布在内质网中；当将WT和Q738X共转染到HEK-293细胞时,虽在胞浆处有部分重叠,但膜上仍有绿色荧光。
2.丙泊酚对WT-hERG钾通道的影响
2.1丙泊酚对WT-hERG钾通道的直接影响
丙泊酚浓度依赖性的抑制WT-hERG钾通道,当浓度为0.01、0.1、1、3、10、30、100、300、1000和3000μM时,丙泊酚对WT-hERG钾通道的抑制率依次为3.8±2.4%、13.9±7.9%、17.0±5.5%、23.2+5.0%、29.8±4.9%、43.7±5.4%、58.2±4.8、66.4±7.5%、71.2±4.3%和84.3+4.1%,丙泊酚抑制WT-hERG钾通道的IC50值为60.9±6.4μM；
使用“尾电流包裹”的实验方法观察10μM丙泊酚对WT-hERG钾通道的时间依赖性,结果显示,随着刺激时程的延长,丙泊酚对WT-hERG钾通道尾电流的抑制程度增加,但大约在1500 ms之后,抑制率达到43.6±3.8%不再有明显增加,说明丙泊酚对WT-hERG钾通道的抑制具有时间依赖性。
观察10μM丙泊酚对WT-hERG钾电流的频率依赖性,在频率为1 Hz时,加药后对WT-hERG钾电流的抑制率为71.0±2.1%；在频率为0.2 Hz时,其抑制率为69.4±2.3%。尽管频率不同,但加药后的电流抑制率经统计学处理,无显著差异(P>0.05),说明丙泊酚对WT-hERG钾电流的抑制无频率依赖性。
通过观察10μM丙泊酚对WT-hERG钾通道动力学的影响,表明10μM丙泊酚对其动力学特性(包括激活、失活和去活)均无影响。
为了解丙泊酚和hERG基因S6区域的两个位点Y652和F656是否具有高亲和力,本实验观察了丙泊酚对突变体Y652A和F656C的作用,结果显示,300μM的丙泊酚对WT-hERG钾通道的抑制率为66.3±7.5%,而对Y652A-hERG钾通道的抑制率仅为21.3±4.1%(P<0.05 vs WT-hERG),丙泊酚抑制Y652A-hERG钾通道电流的IC50值为2871.8±351.9μM；当丙泊酚的浓度为100、300、1000和3000μM时,其对WT-hERG钾通道电流分别抑制了51.0±5.2%、62.4±5.9%、88.4±3.3%和94.7±2.1%；对F656C-hERG钾通道电流分别抑制了8.3±4.5%、21.2±6.3%、39.5±6.7%和45.0±8.3%(P<0.05 vs WT-hERG),可见Y652A和F656C的突变均削弱了丙泊酚抑制WT-hERG钾通道的能力。
2.2丙泊酚对WT-hERG蛋白运输的影响
经Western blot分析和激光共聚焦结果显示丙泊酚对WT-hERG蛋白的表达和定位无影响。
3.丙泊酚对WT/Q738X-hERG钾通道的影响
丙泊酚浓度依赖性的抑制WT/Q738X-hERG钾通道,当浓度为O.1、1、3、10、30、100和1000μM时,丙泊酚依次对WT/Q738X-hERG钾通道的抑制率为2.9±4.9%、11.6±3.8%、33.7+3.2%、48.9±2.5%、55.8±3.8%、80.1±2.9%和87.5±2.9%,丙泊酚抑制WT/Q738X-hERG钾通道的IC50值为14.2±2.8μM,但丙泊酚不改变WT/Q738X-hERG钾通道的激活和失活特性。
1.突变体Q738X可导致hERG蛋白功能的丧失,对野生型WT-hERG钾通道无负显性抑制,属于运输障碍；
2.丙泊酚可直接抑制WT-hERG电流,具有浓度依赖性和时间依赖性,而无频率依赖性,对其动力学特征(激活、失活和去活)无明显影响；丙泊酚与位点Y652和F656有高亲和力；丙泊酚对WT-hERG蛋白的运输无影响；
3.Q738X突变可增强丙泊酚对hERG蛋白的抑制作用。
There are two types of long QT syndrome (LQTS), inherited and acquired LQTS. Inherited LQTS is caused by mutation of genes encoding cardiac ionic channels or associated partners, which leads to dysfunction of corresponding ionic channel proteins. So far, molecular genetic studies have discovered at least ten forms of inherited LQTS numbered in order of discovery as LQT1-LQT10. Mutation in the hERG gene accounting for LQT2 is one of the principal causes of inherited LQTS. The human ether-a-go-go-related gene (hERG) encodes the a-subunit of the rapidly activating delayed rectifier potassium ion channel underlying IKr-and this, current is essential to the repolarization phase of cardiac action potential in the mammalian heart. More recently, Yasuda et al. reported a small family of hereditary LQT2 caused by a novel hERG mutation, showing a wide variety of ECG phenotypes among family members under the common single nucleotide mutation (c.C2212T and p.Q738X). However, the mechanism for hERG channel dysfunction in the Q738X mutation has not been studied.
Acquired LQTS is mainly induced by drugs. The drug-induced LQTS can result from:1. direct block of channel conduction. The drug has high affinity with the particular aromatic amino acid (position Y652 and F656) located on the S6 transmembrane domain of the hERG channel. When it binds with the hERG channel, it leads to K+ efflux decrease in phase 3 repolarization of cardiac cells, and therefore prolongs the length of QT interval.2. Indirect inhibition by disrupting channel protein trafficking. The drug disrupts normal hERG channel protein processing and maturation to reduce its surface membrane expression.
Propofol is a short-acting intravenous anesthetic agent widely used for the induction and maintenance of general anesthesia and for sedation in intensive care units. Despite its commendable record, there have been scattered reports of an association of propofol use with sudden death. Several recent studies investigated the effect of poprofol on QT interval, however these results were conflicting. Some studies reported that propofol prolonged the QT interval. Conversely, other studies found that propofol had no effect or shortened the QT interval. In these studies propofol was administered simultaneously with other agents within a short period of time; therefore, it is difficult to determine its selective effect on the QT interval. To our knowledge, the effect and mechanism of poprofol on the QT interval are not entirely clear but could involve actions on the hERG K+ channel.
So, the objectives of this study are as follows:1. To examine the electrophysiological consequences of the Q738X mutation; 2. To evaluate the effect of propofol on reconstituted wild type (WT) and its underlying mechanism; 3. To evaluate the effect of propofol on mutant hERG channels using the heterologous expression system in HEK-293 cells.
Mutant Q738X, Y652A and F656C-hERG were constructed by overlap extension PCR and were verified by DNA sequencing, respectively.
HEK-293 cells were cultured in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum in a humidified 5% CO2 incubator at 37℃.
For transfection of hERG constructs in different amounts, cells were plated in a culture dish and transfected transiently 24～36 h later with the calcium phosphate precipitation method or lipofectamine method.
Transfected cells were transferred to a bath mounted on the stage of an inverted microscope. First, we studied the current, current-voltage relation, actvation, deactivation and inactivation of WT-hERG and WT/Q738X-hERG channel. Secondly, we observed the effect of propofol on WT-hERG, Y652A, F656C, and WT/Q738X-hERG channel, respectively.
The cells were scrapped in ice-cold phosphate-buffered saline and lysed in RIPA buffer. Protein concentrations were determined by the bicinchoninic acid method. Protein per sample was electrophoresed on 10% Tris-acetate gels and transferred onto PVDF membranes. The membranes were blocked with 5% non-fat dry milk before incubation with rabbit anti-hERG antibody (1:200) overnight. The membranes were then incubated with goat anti-rabbit horseradish peroxidase-conjugated secondary antibody (1:10000) in TBST for 1 h at room temperature. After washing with TBST, the membranes were developed using ECL. Blots were analyzed and quantified by Quantity one software.
At 36～48 h after transfection, HEK293 cells were fixed with 4% paraformaldehyde, treated with 0.1% Triton X-100, blocked with 2% bovine serum albumin (BSA) at room temperature. Cells were then labeled with rabbit polyclonal anti-hERG and chicken polyclonal anti-calreticulin at 4℃overnight followed by incubation with FITC-conjugated goat antirabbit IgG secondary antibody and Alexa fluor-conjugated goat antichicken IgG secondary antibody at 37℃for 2 h.
Immunofluorescence staining was viewed with a confocal laser scanning microscope (excitation and emission wavelength for FITC were 488 and 520nm, respectively; excitation and emission wavelength for Alexa fluor were 633 and 647 nm, respectively).
Data are presented as mean±S.E.M. The data were acquired with use of Pulse 8.67 software and analyzed by SPSS 13.0 and Origin 6.0 software. Statistical comparisons were evaluated by t tests and one-way ANOVA. P values of less than 0.05 were taken as significant.
There were classic currents from HEK-293 cells transfected with WT-hERG, but no currents from cells transfected with Q738X-hERG channel. These cells cotransfected with WT/Q738X-hERG showed currents with similar waveforms but reduced current amplitudes compared to those cells expressing WT-hERG channels alone. The peak tail current of WT-hERG (4μg), WT-hERG (2μg) and WT/Q738X (2μg each) was 59.9±3.2 pA/pF,32.2±1.7 pA/pF and 26.2±3.5 pA/pF (P<0.05 vs 4μg WT-hERG), respectively. Therefore, we conclude the Q738X mutation had no a potent dominant-negative effect on WT-hERG channel properties.
Mutant Q738X had not altered the kinetic features of WT-hERG channel (activation, deactivation and inactivation).
The results of Western blot showed two bands (135 and 155 KDa) in WT-hERG group, only one 135 KDa band in Q738X-hERG group, and both bands, but a weaker 155 KDa band in WT/Q738X-hERG group.
The results of confocal imaging showed WT-hERG mainly expressed in membrane, Q738X-hERG expressed in cytoplasm and WT/Q738X-hERG expressed in both membrane and cytoplasm.
Propofol inhibited WT-hERG channel current in a concentration-dependent manner. When the concentrations of propofol were 0.01,0.1,1,3,10,30,100,300,1000, and 3000μM, the inhibition rates of WT-hERG channel current were 3.8±2.4%, 13.9±7.9%,17.0±5.5%,23.2±5.0%,29.8±4.9%,43.7±5.4%,58.2±4.8%,66.4±7.5%, 71.2±4.3%, and 84.3±4.1%, respectively. The half maximal inhibitory concentration (IC50) of WT-hERG was 60.9±6.4μM.
An "envelope of tails" protocol was used to investigate the time-dependence of propofol block. A significant block was achieved with a 50 ms depolarizing step after application of propofol. The extent of block was further increased with increasing pulse duration and maximal block was achieved at 1500 ms, demonstrating the inhibitory effect of propofol on WT-hERG current was time-dependent.
The frequency dependence of WT-hERG current block was investigated by applying 30 repetitive pulses at 0.2 and 1 Hz. For control conditions, the HERG current amplitude during the pulse train decreased only slightly. Following exposure to 10μM propofol, application of the pulse train at either 0.2 or 1.0 Hz decreased current amplitude by 69.4±2.3% at 0.2 Hz and by 71.0±2.1% at 1 Hz (P>0.05). Thus, the effect of propofol on WT-hERG had no frequence-dependence.
The block of WT-hERG by propofol had not altered the kinetic features of WT-hERG channel (activation, deactivation and inactivation).
At 300μM concentration, propofol inhibited the WT-hERG channel by 66.3±7.5% while inhibited Y652A-hERG channel by 21.3±4.1%(P<0.05 vs WT-hERG). The IC50 value of Y652A-hERG was 2871.8±351.9μM. When the concentrations of propofol were 100,300,1000 and 3000μM, the inhibition rates of WT-hERG channel were 51.0±5.2%,62.4±5.9%,88.4±3.3%, and 94.7±2.1%, respectively, and the inhibition rates of F656C-hERG channel were 8.3±4.5%,21.2±6.3%,39.5±6.7%, and 45.0±8.3%, respectively (P<0.05 vs WT-hERG). Mutations in drug-binding sites (Y652A or F656C) of the hERG channel significantly attenuated the hERG current blockade by propofol.
The results of Western blot and confocal imaging showed that propofol can not affect the protein trafficking of WT-hERG channel.
Propofol blocked WT/Q738X-hERG channel in a concentration-dependent manner. When the concentrations of propofol were 0.1,1,3,10,30,100 and 1000μM, the inhibition of WT/Q738X-hERG were 2.9±4.9%,11.6±3.8%,33.7±3.2%,48.9±2.5%, 55.8±3.8%,80.1±2.9%, and 87.5±2.9%, respectively. The IC50 value of WT/Q738X-hERG was 14.2±2.8μM.
The block of WT/Q738X-hERG by propofol had not altered the kinetic features of WT-hERG channel (activation, inactivation and deactivation).
1. The Q738X mutation of hERG is nonfunctional and has no a dominant-negative effect on WT-hERG current function;
2. Propofol inhibits WT-hERG channel in a concentration-and time-dependent manner, but not frequence-dependent; Propofol have not altered the kinetic features of WT-hERG channel (activation, deactivation, and inactivation); Mutations in drug-binding sites (Y652A or F656C) of the hERG channel attenuate the hERG current blockade by propofol; Propofol does not influence the protein trafficking of WT-hERG channel;
3. Mutant Q738X can increase the inhibition of propofol on WT-hERG.
获得性LQTS主要是由于药物引起,药物主要通过两种机制作用于hERG钾通道：①直接抑制hERG钾通道,药物多与hERG钾通道S6区域的两个芳香族氨基酸Y652和F656具有高的亲和力,引起心肌细胞复极3期K+外流减少；②影响hERG蛋白的运输过程,造成细胞膜表面的hERG蛋白数量减少。
丙泊酚(propofol)又名异丙酚,是一种快速强效的全身麻醉剂,由丙泊酚引起的心电图QT间期延长,导致发作性晕厥、心脏猝死的心律失常事件时有发生。关于丙泊酚对QT间期影响的报道结果不一,一些研究认为丙泊酚能延长QT间期,相反,有些报道认为丙泊酚不影响甚至缩短QT间期。然而,在这些报道中丙泊酚常和其它药物同时使用,很难判定是丙泊酚单独作用的结果。我们假设丙泊酚对QT间期的影响及其机制可能与hERG钾通道的抑制有关。因此,本实验目的：①突变体Q738X-hERG的功能鉴定；②探讨丙泊酚对野生型(wide type, WT) hERG钾通道和共转染型WT/Q738X-hERG钾通道的影响；③丙泊酚对hERG钾通道作用机制的探讨,为临床合理化和个体化用药提供理论依据。方法
1.PCR定点突变Q738X、Y652A和F656C-hERG:采用PCR定点突变技术进行Q738X,Y652A和F656C突变,经DNA测序验证突变成功。
2.细胞培养和瞬时转染：人胚肾上皮细胞(human embryonic kidney cell line,HEK-293细胞)在含10%胎牛血清的高糖DMEM培养基中培养。采用磷酸钙沉淀或脂质体介导的方法进行瞬时转染。根据实验要求,转染质粒包括：①野生型WT-hERG;②突变型Q738X、Y652A和F656C-hERG;③共转染型：WT/Q738X-hERG;④对照组WT-hERG和空白质粒PBI。
3.全细胞膜片钳记录hERG钾通道电流：寻找表达有绿色荧光的单个HEK-293细胞,采用全细胞膜片钳技术,选用不同的实验方案,分别记录野生型WT、突变型Q738X、共转染型WT/Q738X和对照组的hERG钾通道电流和其动力学特征变化,以及丙泊酚对野生型WT、突变型Y652A和F656C和共转染型WT/Q738X-hERG钾通道电流和其动力学特征的变化。
4.Western blot检测hERG蛋白的表达：酶解收集蛋白,BCA法测蛋白含量,RIPA裂解蛋白,10%的SDS-PAGE凝胶电泳,PVDF转膜,5%脱脂牛奶室温封闭,抗hERG抗体(1：200),4℃孵育过夜,HRP标记的二抗(1：10000),室温孵育1 h,ECL显色。通过Quantity one软件分析每条带的灰密度值,与自身内参β-actin条带的灰密度相比,对每条带进行半定量分析。
5.双重细胞免疫荧光：分别观察转染WT、Q738X和WT/Q738X-hERG的HEK-293细胞上hERG蛋白的定位情况以及丙泊酚对WT-hERG蛋白定位的影响,转染36～48 h后4%多聚甲醛固定细胞,0.1%Triton X-100透化,2%牛血清白蛋白封闭,随后加入兔源抗hERG蛋白抗体和鸡源抗肌钙网蛋白抗体,4℃孵育过夜,次日加入FITC标记的山羊抗兔IgG和Alexa fluor 633标记的山羊抗鸡IgG的二抗,封片剂封片。
6.激光共聚焦技术
将细胞免疫荧光染色的HEK-293细胞进行激光共聚焦定位,FITC(绿色)和Alexa fluor(红色)分别用波长488 nm的氩离子激光和633 nm的氦氖离子激光激发。
7.统计学处理
所有数值用mean±S.E.M表示,使用pulse 8.67软件记录和分析通道电流,采用SPSS13.0和Origin6.0软件来拟合曲线和制图,加药前后采用配对t检验,组间比较采用单因素方差分析。P<0.05为差异有显著性。
1.突变体Q738X-hERG的功能鉴定
1.1突变体Q738X-hERG电流的记录
将转染有野生型WT-hERG的HEK-293细胞进行电生理记录,显示出典型的hERG钾电流,由时间依赖性电流和尾电流两部分组成。而在单独表达有突变型Q738X-hERG的HEK-293细胞中记录不到电流。将WT-hERG和Q738X-hERG(各2μg)共转染到HEK-293细胞中时,虽可记录到hERG钾电流,其电流图形也与WT-hERG电流相似,但其电流幅度明显低于WT-hERG (4μg)而与WT-hERG (2μg)电流大小相似。WT-hERG (4μg)、WT-hERG (2μg)和WT/Q738X(各2μg)的尾电流幅度依次为59.94±3.0、32.2±1.7(P<0.05vs 4μg WT-hERG)和26.2±3.5 pA/pF(P<0.05 vs 4μg WT-hERG);通过对WT/Q738X的动力学观察,发现Q738X突变不改变hERG钾通道的动力学特征(包括激活、失活和去活过程)。
1.2突变体Q738X的运输障碍
Western blot结果显示转染野生型WT-hERG的HEK-293细胞中可以检测到二条蛋白质条带(135和155 KDa),而突变体Q738X-hERG只出现135 KDa一个条带,共转染型WT/Q738X-hERG虽出现135和155 KDa二条蛋白质条带,但其155KDa的条带较弱。通过Quantity one软件分析每条带的灰密度值,对每条带进行半定量分析。结果显示,共转染WT/Q738X-hERG虽有成熟的hERG蛋白(155 KDa)的形成,但是表达量少于WT-hERG(P<0.01)。说明Q738X的突变影响hERG蛋白的运输,使其到达细胞膜表面有功能的hERG蛋白数量减少。
双重细胞免疫荧光染色后经激光共聚焦定位显示：转染有WT-hERG的HEK-293细胞,其绿色荧光主要分布在细胞膜上,与ER marker(红光)共定位后,虽有部分重叠,但膜上的绿色荧光仍然很清楚；而转染有突变体Q738X-hERG的HEK-293细胞,其绿色荧光主要分布在胞浆中,与ER marker共定位后,完全重合,说明突变体Q738X-hERG蛋白分布在内质网中；当将WT和Q738X共转染到HEK-293细胞时,虽在胞浆处有部分重叠,但膜上仍有绿色荧光。
2.丙泊酚对WT-hERG钾通道的影响
2.1丙泊酚对WT-hERG钾通道的直接影响
丙泊酚浓度依赖性的抑制WT-hERG钾通道,当浓度为0.01、0.1、1、3、10、30、100、300、1000和3000μM时,丙泊酚对WT-hERG钾通道的抑制率依次为3.8±2.4%、13.9±7.9%、17.0±5.5%、23.2+5.0%、29.8±4.9%、43.7±5.4%、58.2±4.8、66.4±7.5%、71.2±4.3%和84.3+4.1%,丙泊酚抑制WT-hERG钾通道的IC50值为60.9±6.4μM；
使用“尾电流包裹”的实验方法观察10μM丙泊酚对WT-hERG钾通道的时间依赖性,结果显示,随着刺激时程的延长,丙泊酚对WT-hERG钾通道尾电流的抑制程度增加,但大约在1500 ms之后,抑制率达到43.6±3.8%不再有明显增加,说明丙泊酚对WT-hERG钾通道的抑制具有时间依赖性。
观察10μM丙泊酚对WT-hERG钾电流的频率依赖性,在频率为1 Hz时,加药后对WT-hERG钾电流的抑制率为71.0±2.1%；在频率为0.2 Hz时,其抑制率为69.4±2.3%。尽管频率不同,但加药后的电流抑制率经统计学处理,无显著差异(P>0.05),说明丙泊酚对WT-hERG钾电流的抑制无频率依赖性。
通过观察10μM丙泊酚对WT-hERG钾通道动力学的影响,表明10μM丙泊酚对其动力学特性(包括激活、失活和去活)均无影响。
为了解丙泊酚和hERG基因S6区域的两个位点Y652和F656是否具有高亲和力,本实验观察了丙泊酚对突变体Y652A和F656C的作用,结果显示,300μM的丙泊酚对WT-hERG钾通道的抑制率为66.3±7.5%,而对Y652A-hERG钾通道的抑制率仅为21.3±4.1%(P<0.05 vs WT-hERG),丙泊酚抑制Y652A-hERG钾通道电流的IC50值为2871.8±351.9μM；当丙泊酚的浓度为100、300、1000和3000μM时,其对WT-hERG钾通道电流分别抑制了51.0±5.2%、62.4±5.9%、88.4±3.3%和94.7±2.1%；对F656C-hERG钾通道电流分别抑制了8.3±4.5%、21.2±6.3%、39.5±6.7%和45.0±8.3%(P<0.05 vs WT-hERG),可见Y652A和F656C的突变均削弱了丙泊酚抑制WT-hERG钾通道的能力。
2.2丙泊酚对WT-hERG蛋白运输的影响
经Western blot分析和激光共聚焦结果显示丙泊酚对WT-hERG蛋白的表达和定位无影响。
3.丙泊酚对WT/Q738X-hERG钾通道的影响
丙泊酚浓度依赖性的抑制WT/Q738X-hERG钾通道,当浓度为O.1、1、3、10、30、100和1000μM时,丙泊酚依次对WT/Q738X-hERG钾通道的抑制率为2.9±4.9%、11.6±3.8%、33.7+3.2%、48.9±2.5%、55.8±3.8%、80.1±2.9%和87.5±2.9%,丙泊酚抑制WT/Q738X-hERG钾通道的IC50值为14.2±2.8μM,但丙泊酚不改变WT/Q738X-hERG钾通道的激活和失活特性。
1.突变体Q738X可导致hERG蛋白功能的丧失,对野生型WT-hERG钾通道无负显性抑制,属于运输障碍；
2.丙泊酚可直接抑制WT-hERG电流,具有浓度依赖性和时间依赖性,而无频率依赖性,对其动力学特征(激活、失活和去活)无明显影响；丙泊酚与位点Y652和F656有高亲和力；丙泊酚对WT-hERG蛋白的运输无影响；
3.Q738X突变可增强丙泊酚对hERG蛋白的抑制作用。
There are two types of long QT syndrome (LQTS), inherited and acquired LQTS. Inherited LQTS is caused by mutation of genes encoding cardiac ionic channels or associated partners, which leads to dysfunction of corresponding ionic channel proteins. So far, molecular genetic studies have discovered at least ten forms of inherited LQTS numbered in order of discovery as LQT1-LQT10. Mutation in the hERG gene accounting for LQT2 is one of the principal causes of inherited LQTS. The human ether-a-go-go-related gene (hERG) encodes the a-subunit of the rapidly activating delayed rectifier potassium ion channel underlying IKr-and this, current is essential to the repolarization phase of cardiac action potential in the mammalian heart. More recently, Yasuda et al. reported a small family of hereditary LQT2 caused by a novel hERG mutation, showing a wide variety of ECG phenotypes among family members under the common single nucleotide mutation (c.C2212T and p.Q738X). However, the mechanism for hERG channel dysfunction in the Q738X mutation has not been studied.
Acquired LQTS is mainly induced by drugs. The drug-induced LQTS can result from:1. direct block of channel conduction. The drug has high affinity with the particular aromatic amino acid (position Y652 and F656) located on the S6 transmembrane domain of the hERG channel. When it binds with the hERG channel, it leads to K+ efflux decrease in phase 3 repolarization of cardiac cells, and therefore prolongs the length of QT interval.2. Indirect inhibition by disrupting channel protein trafficking. The drug disrupts normal hERG channel protein processing and maturation to reduce its surface membrane expression.
Propofol is a short-acting intravenous anesthetic agent widely used for the induction and maintenance of general anesthesia and for sedation in intensive care units. Despite its commendable record, there have been scattered reports of an association of propofol use with sudden death. Several recent studies investigated the effect of poprofol on QT interval, however these results were conflicting. Some studies reported that propofol prolonged the QT interval. Conversely, other studies found that propofol had no effect or shortened the QT interval. In these studies propofol was administered simultaneously with other agents within a short period of time; therefore, it is difficult to determine its selective effect on the QT interval. To our knowledge, the effect and mechanism of poprofol on the QT interval are not entirely clear but could involve actions on the hERG K+ channel.
So, the objectives of this study are as follows:1. To examine the electrophysiological consequences of the Q738X mutation; 2. To evaluate the effect of propofol on reconstituted wild type (WT) and its underlying mechanism; 3. To evaluate the effect of propofol on mutant hERG channels using the heterologous expression system in HEK-293 cells.
Mutant Q738X, Y652A and F656C-hERG were constructed by overlap extension PCR and were verified by DNA sequencing, respectively.
HEK-293 cells were cultured in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum in a humidified 5% CO2 incubator at 37℃.
For transfection of hERG constructs in different amounts, cells were plated in a culture dish and transfected transiently 24～36 h later with the calcium phosphate precipitation method or lipofectamine method.
Transfected cells were transferred to a bath mounted on the stage of an inverted microscope. First, we studied the current, current-voltage relation, actvation, deactivation and inactivation of WT-hERG and WT/Q738X-hERG channel. Secondly, we observed the effect of propofol on WT-hERG, Y652A, F656C, and WT/Q738X-hERG channel, respectively.
The cells were scrapped in ice-cold phosphate-buffered saline and lysed in RIPA buffer. Protein concentrations were determined by the bicinchoninic acid method. Protein per sample was electrophoresed on 10% Tris-acetate gels and transferred onto PVDF membranes. The membranes were blocked with 5% non-fat dry milk before incubation with rabbit anti-hERG antibody (1:200) overnight. The membranes were then incubated with goat anti-rabbit horseradish peroxidase-conjugated secondary antibody (1:10000) in TBST for 1 h at room temperature. After washing with TBST, the membranes were developed using ECL. Blots were analyzed and quantified by Quantity one software.
At 36～48 h after transfection, HEK293 cells were fixed with 4% paraformaldehyde, treated with 0.1% Triton X-100, blocked with 2% bovine serum albumin (BSA) at room temperature. Cells were then labeled with rabbit polyclonal anti-hERG and chicken polyclonal anti-calreticulin at 4℃overnight followed by incubation with FITC-conjugated goat antirabbit IgG secondary antibody and Alexa fluor-conjugated goat antichicken IgG secondary antibody at 37℃for 2 h.
Immunofluorescence staining was viewed with a confocal laser scanning microscope (excitation and emission wavelength for FITC were 488 and 520nm, respectively; excitation and emission wavelength for Alexa fluor were 633 and 647 nm, respectively).
Data are presented as mean±S.E.M. The data were acquired with use of Pulse 8.67 software and analyzed by SPSS 13.0 and Origin 6.0 software. Statistical comparisons were evaluated by t tests and one-way ANOVA. P values of less than 0.05 were taken as significant.
There were classic currents from HEK-293 cells transfected with WT-hERG, but no currents from cells transfected with Q738X-hERG channel. These cells cotransfected with WT/Q738X-hERG showed currents with similar waveforms but reduced current amplitudes compared to those cells expressing WT-hERG channels alone. The peak tail current of WT-hERG (4μg), WT-hERG (2μg) and WT/Q738X (2μg each) was 59.9±3.2 pA/pF,32.2±1.7 pA/pF and 26.2±3.5 pA/pF (P<0.05 vs 4μg WT-hERG), respectively. Therefore, we conclude the Q738X mutation had no a potent dominant-negative effect on WT-hERG channel properties.
Mutant Q738X had not altered the kinetic features of WT-hERG channel (activation, deactivation and inactivation).
The results of Western blot showed two bands (135 and 155 KDa) in WT-hERG group, only one 135 KDa band in Q738X-hERG group, and both bands, but a weaker 155 KDa band in WT/Q738X-hERG group.
The results of confocal imaging showed WT-hERG mainly expressed in membrane, Q738X-hERG expressed in cytoplasm and WT/Q738X-hERG expressed in both membrane and cytoplasm.
Propofol inhibited WT-hERG channel current in a concentration-dependent manner. When the concentrations of propofol were 0.01,0.1,1,3,10,30,100,300,1000, and 3000μM, the inhibition rates of WT-hERG channel current were 3.8±2.4%, 13.9±7.9%,17.0±5.5%,23.2±5.0%,29.8±4.9%,43.7±5.4%,58.2±4.8%,66.4±7.5%, 71.2±4.3%, and 84.3±4.1%, respectively. The half maximal inhibitory concentration (IC50) of WT-hERG was 60.9±6.4μM.
An "envelope of tails" protocol was used to investigate the time-dependence of propofol block. A significant block was achieved with a 50 ms depolarizing step after application of propofol. The extent of block was further increased with increasing pulse duration and maximal block was achieved at 1500 ms, demonstrating the inhibitory effect of propofol on WT-hERG current was time-dependent.
The frequency dependence of WT-hERG current block was investigated by applying 30 repetitive pulses at 0.2 and 1 Hz. For control conditions, the HERG current amplitude during the pulse train decreased only slightly. Following exposure to 10μM propofol, application of the pulse train at either 0.2 or 1.0 Hz decreased current amplitude by 69.4±2.3% at 0.2 Hz and by 71.0±2.1% at 1 Hz (P>0.05). Thus, the effect of propofol on WT-hERG had no frequence-dependence.
The block of WT-hERG by propofol had not altered the kinetic features of WT-hERG channel (activation, deactivation and inactivation).
At 300μM concentration, propofol inhibited the WT-hERG channel by 66.3±7.5% while inhibited Y652A-hERG channel by 21.3±4.1%(P<0.05 vs WT-hERG). The IC50 value of Y652A-hERG was 2871.8±351.9μM. When the concentrations of propofol were 100,300,1000 and 3000μM, the inhibition rates of WT-hERG channel were 51.0±5.2%,62.4±5.9%,88.4±3.3%, and 94.7±2.1%, respectively, and the inhibition rates of F656C-hERG channel were 8.3±4.5%,21.2±6.3%,39.5±6.7%, and 45.0±8.3%, respectively (P<0.05 vs WT-hERG). Mutations in drug-binding sites (Y652A or F656C) of the hERG channel significantly attenuated the hERG current blockade by propofol.
The results of Western blot and confocal imaging showed that propofol can not affect the protein trafficking of WT-hERG channel.
Propofol blocked WT/Q738X-hERG channel in a concentration-dependent manner. When the concentrations of propofol were 0.1,1,3,10,30,100 and 1000μM, the inhibition of WT/Q738X-hERG were 2.9±4.9%,11.6±3.8%,33.7±3.2%,48.9±2.5%, 55.8±3.8%,80.1±2.9%, and 87.5±2.9%, respectively. The IC50 value of WT/Q738X-hERG was 14.2±2.8μM.
The block of WT/Q738X-hERG by propofol had not altered the kinetic features of WT-hERG channel (activation, inactivation and deactivation).
1. The Q738X mutation of hERG is nonfunctional and has no a dominant-negative effect on WT-hERG current function;
2. Propofol inhibits WT-hERG channel in a concentration-and time-dependent manner, but not frequence-dependent; Propofol have not altered the kinetic features of WT-hERG channel (activation, deactivation, and inactivation); Mutations in drug-binding sites (Y652A or F656C) of the hERG channel attenuate the hERG current blockade by propofol; Propofol does not influence the protein trafficking of WT-hERG channel;
3. Mutant Q738X can increase the inhibition of propofol on WT-hERG.
引文
[1]Moss AJ, Robinson JL. The long-QT syndrome[J]. Circulation,2002,105:784-792.
[2]Roden DM. Clinical practice. Long-QT syndrome[J]. N Engl J Med,2008,358(2):169-76.
[3]Keating MT, Sanguinitti MC. Molecular and cellular mechanisms of cardiac afthvthmias[J]. Cell,2001,104:569-580.
[4]Schwartz PJ. The congenital long QT syndromes from genotype to phenotype:clinical implications[J]. J Intern Med,2006,259(1):39-47.
[5]Splawski I, Shen J, Timothy KW, et al. Spectrumof mutations in long QT syndrome genes KVLQT1, HERG, SCN5A, KCNE1 and KCNE2[J]. Circulation,2000,102(1):1178-1185.
[6]Mohler PJ, Schott JJ, Gramolini AO, et al. Ankyrin2B mutation causes type 4 long-QT cardiac arrhythmia and sudden cardiac death[J]. Nature,2003,421(6923):634-639.
[7]Tsuboi M, Antzelevitch C. Cellular basis for electrocardiographic and arrhythmic manifestation of Andersen-Tawil syndrome (LQT7)[J]. Heart Rhythm,2006,3(3):328-335.
[8]Shimizu W. The long QT syndrome:therapeutic implications of a genetic diagnosis[J]. Cardiovasc Res,2005,67(3):347-356.
[9]Ye B, Tester DJ, Vatta M, et al. Molecular and functional characterization of novel cav3-encoded caveolin-3 mutations in congenital long QT syndrome, (abst AB1-1) [J]. Heart Rhythm,2006,3(Suppl):S1.
[10]Domingo AM, Kaku T, Tester DJ, et al. Sodium channel b4 subunit mutation causes congenital long QT syndrome.(abst AB16-6) [J]. Heart Rhyth,2006,3(Suppl):S34.
[11].Roy M, Dumaine R, Brown AM. HERG, a primary human ventricular target of the nonsedating antihistamine terfenadine[J]. Circulation,1996,94(4):817-823.
[12]李翠兰,张莉,胡大一等.85例中国人长QT综合征先证者的临床特征及有关基因突变研究现状[J].中华心律失常学杂志,2004,8(6)：328-334.
[13]Keller DI, Grenier J, Christe G, et al. Characterization of novel KCNH2 mutations in type 2 long QT syndrome manifesting as seizures[J]. Can J Cardiol,2009,25(8):455-462.
[14]Surran ME, Splawski I, Timothy KW, et al. A molecular basis for cardiac arrhythmia:HERG mutations cause long QT syndrome[J]. Cell,1995,80(5):795-803.
[15]Sanguinetti MC, Jiang C, Curran ME, et al. A mechanistic link between an inhefited and an acquired cardiac arrhythmia:HERG encodes the IKr potassium channel [J]. Cell,1995,81(2): 299-307.
[16]Yasuda S, Hiramatsu SI, Odashiro K, et al. A family of hereditary long QT syndrome caused by Q738X HERG mutation[J]. Int J Cardiol,2009,19. [Epub ahead of print].
[17]Huo J, huang N, Huang C, et al. The G604S-hERG mutation alters the biophysical properties and exerts a dominant-negative effect on expression of hERG channels in HEK293 cells[J]. Pflugers Arch,2008,456(5):917-928.
[18]Zhou ZF, Gong QM, Epstein ML, et al. HERG channel dysfunction in human long QT syndrome Intracellular transport and functional defects[J]. J Biol Chem,1998,273(3): 21061-21066.
[19]Wang L, Dennis AT, Trieu P, et al. Intracellular potassium stabilizes human ether-a-go-go-related gene channels for export from endoplasmic reticulum[J]. Mol Pharmacol,2009,75(4):927-937.
[20]Delisle BP, Anson BD, Rajamani S, et al. Biology of cardiac an'hythmias:ion channel protein traficking[J]. Circ Res,2004,94(11):1418-1428.
[21]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1 (hERG) current by a class 2 (trafficking-deficient) mechanism[J], Circulation,2006,113(3):365-373.
[22]Chen J, Zou A, Splawski I, et al. Long QT syndrome-associatedmutations in the Per-Arut-Sim (PAS) domain of HERG potassium channels accelerate channel deactivation[J]. J Biol Chem,1999,274(15):L0113-L0118
[23]Nakajima T, Furukawa T, Hiraoka M. Voltage-shift of the current activation in HERG S4 mutation (R534C) in LQT2[J]. Cardiovasc Res,1999,44(2):283-293.
[24]Lees-Miller JP, Duan Y, Teng GQ, et al. Novel gain-of-function mechanism in K+ channel-related long-QT syndrome:altered gating and selectivity in the HERG1 N629D mutant[J]. Circ Res,2000,86(5):507-513.
[25]Kupershmidt S, Yang T, Chanthaphaychith S, et al. Defective human ether-a-go-go-related gene trafficking linked to an endoplasmic reticulum retention signal in the C terminus[J]. J Biol Chem,2002,277(30):27442-27448.
[26]Akhavan A, Atanasiu R, Shrier A. Identification of a COOH-terminal segmentinvolved in maturation and stability of human ether-a-go-go-related gene potassium channels[J]. J Biol Chem,2003,278(41):40105-40112.
[27]Zhao JT, Hill AP, Varghese A, et al. Not all hERG pore domain mutations have a severe phenotype:G584S has an inactivation gating defect with mild phenotype compared to G572S, which has a dominant negative trafficking defect and a severe phenotype[J]. J Cardiovasc Electrophydilo,2009,20(8):923-930.
[28]Hsueh CH, Chen WP, Lin JL, et al. Functional studies on three novel HCNH2 mutations in Taiwan:Identification of distinct mechanisms of channel defect and dissociation between glycosylation defect and assembly defect[J]. Biochem Biophys Res Commun,2008,373(4): 572-578.
[29]Nademanee K. Genotype-Phenotype Relationship in the Long QT Syndrome[J]. J Am Coll Cardiol,2009,54:2063-2064.
[30]Shimizu W, Moss AJ, Wilde AAM, et al. Genotype-phenotype aspects of type 2 long QT syndrome[J]. J Am Coll Cardiol,2009,54(2):2052-2062.
[31]Redfern WS, Carlsson L, Davis AS, et al. Relationships between preclinical cardiac electrophysiology, clinical QT interval prolongation and torsade de pointes for a broad range of drugs:evidence for a provisional safety margin in drug development. Cardiovasc Res. 2003; 58(1):32-45.
[32]Thomas D, Kiehn J, Katus HA, et al. Defective protein trafficking in hERG associated hereditary long QT syndrome (LQT2):molecular mechanisms and restoration of intracellular protein processing[J]. Cardiovasc Res,2003,60(2):235-241.
[33]Gong Q, Keeney DR, Robinson JC, et al. Defective assembly and trafficking of mutant HERG channels with C-terminal truncations in long QT syndrome[J]. J Mol Cell Cardiol, 2004,37(6):1225-1233.
[34]Sasano T, Ueda K, Orikabe M, et al. Hiraoka, Novel C-terminus frameshift mutation, 1122fs/147, of HERG in LQT2:additional amino acids generated by frameshift cause accelerated inactivation[J]. J Mol Cell Cardiol,2004,37(6):1205-1211.
[35]Aydar E, Palmer C. Functional characterization of the C-terminus of the human ether-a-go-go-related gene K+ channel (HERG)[J]. J Physiol,2001,534(Ptl):1-14.
[1]Calderone V, Cavero I. Ventricular arrhythmias. A potential risk associated with the use of non-cardiovascular drugs prolonging the QT interval[J]. M inerva Med,2002,93(3):181-197.
[2]Bajanowski T, Rossi L, Biondo B, et al. Prolonged QT interval and sudden infant death--report of two cases[J]. Forensic Sci Int,2001,115(1-2):147-153.
[3]Numaguchi H, Johnson JP, Petersen CI, et al. A sensitive mechanism for cation modulation of potassium current[J]. Nat Neurosci,2000,3(5):429-430.
[4]Gordon E, Panaghie G, Deng L, et al. A KCNE2 mutation in a patient with cardiac arrhythmia induced by auditory stimuli and serum electrolyte imbalance[J]. Cardiovasc Res,2008,77(1): 98-106.
[5]Ayangade-Johnson G, Villafane J. Long QT interval resembling long QT syndrome in a newborn with electrolyte dysbalance[J]. J Ky Med Assoc,2001,99(7):285-287.
[6]Coumel P, Leclercq JF, Lucet V. Possible mechanisms of the arrhythmias in the long QT syndrome[J]. Eur Heart J,1985,6 Suppl D:115-129.
[7]Okeahialam BN, Sani MU. Heart disease in HIV/AIDS. How much is due tocachexia[J]? Afr J Med Med Sci,2006,35(Suppl):99-102.
[8]Hrovatin E, Zardo F, Brieda M, et al. Long QT and torsade de pointes in a patient with acquired human immunodeficiency virus infection in multitherapy with drugs affecting cytochrome P450[J]. Ital Heart J Suppl,2004,5:735-740.
[9]Van der Heyden MA, Smits ME, Vos MA. Drugs and trafficking of ion channels:A new pro-arrhythmic threat on the horizon[J]? Br J Pharmacol,2008,153(3):406-409.
[10]Lehtonen A, Fodstad H, Laitinen-Forsblom P, et al. Further evidence of inherited long QT syndrome gene mutations in antiarrhythmic drug-associated torsades de pointes[J]. Heart Rhythm,2007,4(5):603-607.
[11]Cheng HC, Incardona J. Models of torsades de pointes:effects of FPL64176, DPI201106, dofetilide, and chromanol 293B in isolated rabbit and guinea pig hearts[J]. J Pharmacol Toxicol Methods,2009.60(2):174-184.
[12]Drici MD, Barhanin J. Cardiac K+ channels and drug-acquired long QT syndrome[J]. Therapie,2000,55(1):185-93.
[13]Su Z, Chen J, Ruth L. et al. Block of hERG channel by ziprasidone:Biophysical properties and molecular determinants[J]. Biochem pharmacol,2006,71(3):278-286.
[14]Park SJ, Kim KS, Kim EJ. Blockade of HERG K+ channel by an antihistamine drug brompheniramine requires the channel binding within the S6 residue Y652 and F656 [J]. Appl. Toxicol,2008,28(2):104-111.
[15]Ray WA, Murray KT, Meredith S, et al. Oral erythromycin and the risk of sudden death from cardiac causes[J]. N Engl J Med,2004,351(11):1089-1096.
[16]Huang BH, Wu CH, Hsia CP, et al. Azithromycin-induced torsade de pointes[J].Pacing Clin Electro physiol,2007,30(2):1579-1582.
[17]Kuryshev YA, Ficker E, Wang L, et al. Pentamidine-induced long QT syndrome and block of hERG trafficking[J]. J Pharmacol Exp Ther,2005,312(1):316-323.
[18]Paakkari I. Cardiotoxicity of new antihistamines and cisapride[J].Toxicol Lett,2002,127(1-3): 279-284.
[19]Zhou Z, Vorperian VR, Gong Q, et al. Block of HERG potassium channels by the antihistamine astemizole and its metabolites desmethylastemizole and norastemizol[J]. J Cardiovasc Electrophysiol,1999,10(6):836-843.
[20]Gongadze N, Kezeli T, Antelava N. Prolong QT interval and "torsades de pointes" associated with different group of drugs[J]. Georgian Med News,2007,153:45-49.
[21]Kamiya K, Niwa R, Morishima M, et al. Molecular determinants of hERG channel block by terfenadine and cisapride[J]. J Pharmacol Sci,2008,108(3):1-8.
[22]Morissette P, Hreiche R, Turgeon J. Drug-induced long QT syndrome and torsade de pointes[J]. Can J Cardiol,2005,21(10):857-864.
[23]Honig PK, Woosley RL, Zamani K, et al. Changes in the pharmacokinetics andelectrocardiographic pharmacodynamics of terfenadine with concomitant administration of erythromycin[J]. Clin Pharmacol Ther,1992,52(3):231-238.
[24]Patmore L, Fraser S, Mair D, et al. Effects of sparfloxacin, grepafloxacin, moxi-floxacin, and ciprofloxacin on cardiac action potential duration[J]. Eur J Pharmacol,2000,406(3):449-452.
[25]Saarnivaara L, Klemola UM, Lindgren L, et al. QT interval of the ECG, heart rate and arterial pressure using propofol, methohexital or midazolam for induction of anaesthesia[J]. Acta Anaesthesiol. Scand,1990,34(4):276-281.
[26]Cremer OL, Moons KG, Bouman EA, et al. Long-term propofol infusion and cardiac failure in adult head-injured patients[J]. Lancet,2001,357(9250):117-118.
[27]Ernest D, French C. Propofol infusion syndrome-report of an adult fatality[J]. Anaesth Intensive Care,2003,31(3):316-319.
[28]Forbes RB, Morton GH. Ventricular fibrillation in a patient with unsuspected mitral valve prolapse and a prolonged Q-T interval[J]. Can. Anaesth. Soc. J,1979,26(5):424-427.
[29]Kies SJ, Pabelick CM, Hurley HA, et al. Anesthesia for patients with congenital long QT syndrome[J]. Anesthesiology,2005,102(1):204-210
[30]Kleinsasser A, Kuenszberg E, Loeckinger A, et al. Sevoflurane, but not propofol, significantly prolongs the Q-T interval[J]. Anesth. Analg,2000,90(1):25-27
[31]Whyte SD, Booker PD, Buckley DG. The effects of propofol and sevoflurane on the QT interval and transmural dispersion of repolarization in children[J]. Anesth Analg,2005,100(1): 71-77.
[32]Paventi S, Santevecchi A, Ranieri R. Effects of sevoflurane versus propofol on QT interval[J]. Minerva. Anestesiol,2001,67(9):637-640.
[33]Kleinsasser A, Loeckinger A, Lindner KH, et al. Reversing sevoflurane-associated QTc prolongation by changing to propofol[J]. Anaesthesia,2001,56(3):248-250.
[34]Yamada M, Hatakeyama N, Malykhina AP, et al. The effects of sevoflurane and propofol onQT interval and heterologously expressed human ether-a-go-go related gene currents inXenopus oocytes[J]. Anesth. Analg,2006,102(1):98-103.
[35]Wang L, Wible BA, Wan X, et al. Cardiac glycosides as novel inhibitors of human ether-a-go-go-related gene channel trafficking[J]. J. Pharmacol Exp Ther,2007,320(2): 525-534.
[36]Takemasa H, Nagatomo T, Abe H, et al. Coexistence of hERG current block and disruption of protein trafficking in ketoconazole-induced long QT syndrome[J]. Br J Pharmacol,2008,153(3)：439-447.
[37]Kamiya K, Niwa R, Mitcheson JS, et al. Molecular determinants of HERG channel block[J]. Mol Pharmacol,2006,69(5):1709-1716.
[38]Kikuchi K, Nagatomo T, Abe H, et al. Blockade of HERG cardiac K+ current by antifungal drug miconazole[J]. Br J Pharmacol,2005,144,840-848.
[39]International conference on Harmonization. S7B:the nonclinical evaluation of the potential for delayed ventricular repolarization (QTinterval prolongation) by humane pharmaccuticals. 2005
[40]International conference on Harmonization. E14:the clinical evaluation of QT/QTc interval prolongation and proarrhythmic potential for non-antiarrhythmic drugs.2005,7
[41]国家食品药品监督管理局.[H]GPT3-1《化学药物一般药理学研究技术指导原则》[S],.2005.
[42]Huo J, Huang N, Huang C, et al. The G604S-hERG mutation alters the biophysical properties dominant-negative effect on expression of hERG channels in HEK-293 cells[J]. Pfluegers Archiv,2008,456(5):917-928.
[43]Li BX, Yang BF, Zhou J, et al. Inhibitory effects of berberine on IK1, IK, and HERG channels of cardiac myocytes[J]. Acta Pharmacol Sin,2001,22(2):125-131.
[44]Thomas D, Kiehn J, Katus HA, et al. Defective protein trafficking in hERG-associated hereditary long QT syndrome (LQT2):Molecular mechanisms and restoration of intracellular protein processing[J]. Cardiovasc Res,2003,60(2):235-241.
[45]Wang L, Dennis AT, Trieu P, et al. Intracellular potassium stabilizes human ether-a-go-go-related gene channels for export from endoplasmic reticulum[J]. Mol Pharmacol,2009,75(4):927-937.
[46]Roti EC, Myers CD, Ayers RA, et al. Interactions with GM130 during hERG ion channel trafficking. Disruption by type 2 congenital long QT syndrome mutations[J]. J Biol Chem, 2002,277(49):47779-47785.
[47]Cordes JS, Sun Z, Lloyd DB, et al. Pentamidine reduces HERG expression to prolong the QT interval[J]. Br J Pharmacol,2005,145(1):15-23.
[48]Ficker E, Kuryshev YA, Dennis AT, et al. Mechanisms of arsenic-induced prolongation of cardiac repolarization[J]. Mol Pharmacol,2004,66(1):33-44.
[49]Guo J, Massaeli H, Li W, et al. Identification of IKr and its trafficking disruption induced by probucol in cultured neonatal rat cardiomyocytes[J]. J. Pharmacol. Exp. Ther,2007,321(3): 911-920.
[50]Rajamani S, Eckhardt LL, Valdivia CR, et al. Drug-induced long QT syndrome:hERG K+ channel block and disruption of protein trafficking by fluoxetine and norfluoxetine[J]. Br. J. Pharmacol,2006,149(5):481-489.
[51]Scherer D, Hassel D, Bloehs R, et al:Selective noradrenaline reuptake inhibitor atomoxetine directly blocks hERG currents[J]. Br J Pharmacol,2009,156(2):226-236.
[52]Sun H, Liu X, Xiong Q, et al. Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking[J]. J Biol Chem,2006,281(9):5877-5884.
[53]Thomas D, Bloehs R, Koschny R, et al. Doxazosin induces apoptosis of cells expressing hERG potassium channels[J]. Eur J Pharmacol,2008,579(1-3):98-103.
[54]Obers S, Staudacher I, Ficker E, et al. Multiple mechanisms of hERG liability:K(+) current inhibition, disruption of protein trafficking, and apoptosis induced by amoxapine[J]. Naunyn-Schmied Arch Pharmacol,2010,13. [Epub ahead of print]
[55]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1(hERG) current by a class 2 (trafficking-deficient) mechanism[J]. Circulation,2006,113:365-373.
[56]Staudacher I, Schweize PA, Katus HA, et al. hERG:Protein trafficking and potential for therapy and drug side effects[J]. Current Opin Drug Discov Dev,2010,13(1):23-30.
[57]Hatakeyama N, Sakuraya F, Matsuda N, et al. Pharmacological significance of the blocking action of the intravenous general anesthetic propofol on the slow component of cardiac delayed rectifier K+ current[J]. J Pharmacol Sci,2009,110(3):334-343
[58]Thomas D, Wendt-Nordahl G, Rockl K, et al. High-affinity blockade of human ether-a go-go-related gene human cardiac potassium channels by the novel antiarrhythmic drug BRL-32872[J]. J Pharmacol Exp Ther,2001,297(2):753-761.
[59]张莹,庄心良,李士通等.丙泊酚、硫喷妥钠对大鼠心肌细胞钙、钾通道电流的影响[J].中华麻醉学杂志,2004,24(9)：673-676.
[60]Wang H, Zhang Y, Cao L, et al. HERG K+ channel, a regulator of tumor cell apoptosis and proliferation[J]. Cancer Res,2002,62(17):4843-4848.
[61]Goldenberg I, Moss AJ, Bradley J, et al. Long-QT syndrome after age 40. Circulation.2008, 117(17):2192-2201.
[62]Zeltser D, Justo D, Halkin A, et al. Torsade de pointes due to noncardiac drugs:most patients have easily identifiable risk factors[J]. Medicine,2003,82(4):282-290.
[63]Amin AS, Herfs LJ, Delisle BP, et al. Fever-induced QTc prolongation and ventricular arrhythmias in individuals with type 2 congenital long QT syndrome. J Clinical Invest,2008, 18(7):2552-2561.
[64]Ping Y, Kanki H, Drolet B, et al. Allelic variants in long-QT disease genes in patients with drug-associated torsade de points. Circulation,2002,105:1943.
[65]Odening KE, Hyder O, Chaves L, et al. Pharmacogenomics of anesthetic drugs in transgenic LQT1 and LQT2 rabbits reveal genotype-specific differential effects on cardiac repolarization[J]. Am J Physiol Heart Circ Physiol,2008,295(6):H2264-H2272.
[1]Van der Heyden MA, Smits ME, Vos MA. Drugs and trafficking of ion channels:A new pro-arrhythmic threat on the horizon[J]? Br J Pharmacol,2008,153(3):406-409.
[2]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K(+) channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun.,2010, 394(3):536-541.
[3]Gongadze N, Kezeli T, Antelava N. Prolong QT interval and "torsades de pointes" associated with different group of drugs[J]. Georgian Med News,2007, (153):45-49.
[4]Sanguinetti MC, Tristani FM. hERG potassium channels and cardiac arrhythmia[J]. Nature, 2006,440(7083):463-469.
[5]Fernandez D, Ghanta A, Kauffman GW, et al. Physicochemical features of the HERG channel drug binding site[J]. J Biol Chem,2004,279(11):10120-10127.
[6]Zhi Su, Jun Chen, Ruth L, et al. Block of hERG channel by ziprasidone:Biophysical properties and molecular determinants[J]. Biochem Pharmacol,2006,71(3):278-286.
[7]Tang Q, Li ZQ, Li W, et al. The 5-HT2 antagonist ketanserin is an open channel blocker of human cardiac ether-a-go-go-related gene (hERG) potassium channels[J]. Bri J Pharmacol, 2008,155(3):365-373.
[8]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K+ channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun,2010,4: [Epub ahead of print]
[9]Duncan RS, McPate MJ, Ridley JM, et al. Inhibition of the HERG potassium channel by the tricyclic antidepressant doxepin. biochem pharm[J].2007,74(3):425-437.
[10]Rajamani S, Shryock JC, Belardinelli L. Rapid kinetic interactions of ranolazine with HERG K+ current[J]. J Cardiovasc Pharmacol,2008,51(6):581.
[11]Thomas D, Bloehs R, Koschny R, et al. Doxazosin induces apoptosis of cells Expressing hERG K+ channels[J]. Eur J Pharmacol,2008,579(1-3):98-103.
[12]Kim KS, Kim EJ, Lee HA, et al. Effect of sibutramine HCl on cardiac hERG K+ channel[J]. Mol Cell Biochem,2009,320(1-2):125-131.
[13]Witchel HJ, Dempsey CE, Sessions RB, et al. The low-potency, voltage-dependent HERG blocker propafenone-molecular determinants and drug trapping[J]. Mol Pharmacol,2004, 66(5):1201-1212.
[14]Mitcheson JS, Chen J, Lin M, et al. A structural basis for drug-induced long QT syndrome[J]. Proc Natl Acad Sci U S.2000,97(22):12329-12333.
[15]Sanchez-Chapula JA, Ferrer T, Navarro-Polanco RA, et al. Voltage-dependent profile of human ether-a-go-go-related gene channel block is influenced by a single residue in the S6 transmembrane domain[J]. Mol Pharmacol,2003,63(5):1051-1058.
[16]Thomas D, Hammeding BC,Wu K. et al. Inhibition of cardiac HERG currents by the DNA topoisomerase Ⅱ inhibitor amsacrine:mode of action[J]. Br J Phannacol,2004,142(3): 485494.
[17]Thomas D, Wimmer AB, Wu K, et al. Inhibition of human ether-ago-go-related gene potassium channels by alpha 1-adrenoceptor antagonists prazosin, doxazosin, and terazasin[J]. Naunyn Schmiedebergs Arch Pharmacol,2004,369(5):462-472.
[18]Sanchez-Chapula JA, Navan-Polataeo RA, Sanguinetti MC. Block of wild-type and inactivation--deficient human ether-a-go-go-mlmed gene K+ channels by halofantrine[J]. Naunyn Schmiedebergs Arch Pharmacol,2004,370(6):484-491.
[19]Viskin S. Long QT syndromes and torsade de pointes[J]. Lancet,1999,354 (9190): 1625-1633.
[20]Kikuchl K, Nagatomo T, Abe H, et al. Blockade of HERG cardiac K+ current by antifungal drug miconzole[J]. Br J Pharmacol,2005,144(6):840-848.
[21]Lees-Miller JP, Dean Y, Teng GQ, et al. Moleclllar determinant of higt-affinity dofetilide binding to HERGl expressed in Xenopus occytes:involvement of S6 sites[J]. Phannacol,2000, 57(2):367-374.
[22]Perry M, de Groot MJ, Helliwell R, et al. Structural determinants of HERG channel block by clofilium and ibutilide[J]. Mol Pbarmacol,2004,66(2):240-249.
[23]Recanatini M, Cavalli A, Masetti M. Modeling HERG and its interactions with drugs:recent advances in light of current potassium channel simulations[J]. Chem. Med. Chem.2008,3(4): 523-535.
[24]Aronov AM. Ligand structural aspects of hERG channel blockade[J]. Curr Top Med Chem. 2008,8(13):1113-1127.
[1]Sanguinetti MC, Jurkiewicz NK. Two components block of delayed rectifier of cardiac delayed rectifier K+ current.differential sensitivity to block by class III anti-arrhythmic agents[J]. J Gen Physiol,1990,96(1):195-215.
[2]Sanguinetti MC, Jurkiewicz NK. Delayed rectifier outward K+ current is composed of two currents in guinea pig atrial cells[J]. Am J Physiol,1991,260(2):H393-H399.
[3]Liu S, Rasmusson RL, Campbell DL, et al. Activation and inactivation kinetics of an E-4031-sensitive current from single ferret atrial myocytes[J]. Biophys J,1996,70(6): 2704-2715.
[4]Davies MP, An RH, Doevendans P, et al. Developmental changes in ionic channel activity in the embryonic mouse heart[J]. Cir Res,1996,78(1):15-25.
[5]Wang L, Feng ZP, Kondo CS, et al. Developmental changes in the delayed rectifier K+ channels in mouse heart[J]. Circ Res,1996,79(1):79-85.
[6]Wymore RS, Gintant GA, Wymore RT, et al. Tissue and species distribution of mRNA for the IKr-like K+ channel, erg[J]. Circ Res,1997,80(2):261-268.
[7]Follmer CH, Colatsky TJ. Block of delayed rectifier potassium current, Ik, by flecainide and E-4031 in cat ventricular myocytes[J]. Circulation,1990,82(1):289-293.
[8]Cordeiro JM, Spitzer KW, Giles WR. Repolarizing K+ currents in rabbit heart Purkinje cells[J]. J Physiol,1998,508(3):811-823.
[9]Gintant GA. Two components of delayed rectifier current in canine atrium and ventricle. Does IKs play a role in the reverse rate dependence of class III agents[J]? Circ Res,1996,78(1): 26-37.
[10]Wang Z, Fermini B, Nattel S. Rapid and slow components of delayed rectifier current in human atrial myocytes[J]. Cardiov Res,1994,28(10):1540-1546.
[11]Li GR, Feng J, Yue L, et al. Evidence for two components of delayed rectifier K+ current in human ventricular myocytes[J]. Circ Res,1996,78(4):689-696.
[12]Warmke JW, Ganetzky B. A family of potassium channel genes related to eag in Drosophila and mammals[J]. Proc. Natl. Acad. Sci. USA,1994,91(8):3438-3442.
[13]Sanguinetti MC, Jiang C, Curran ME, et al. A mechanistic link between an inherited and an acquired cardiac arrhythmia:HERG encodes the IKr potassium channel[J]. Cell,1995,81(2): 299-307.
[14]Trudeau MC, Warmke JW, Ganetzky B, et al. HERG, a human inward rectifier in the voltage-gated potassium channel family[J]. Science,1995,269(5220):92-95.
[15]Morais Cabral JH, Lee A, Cohen SL, et al. Crystal structure and functional analysis of the HERG potassium channel N terminus:a eukaryotic PAS domain[J]. Cell,1998,95(5): 649-655.
[16]Liu J, Zhang M, Jiang M, et al. Structural and functional role of the extracellular S5-P linker in the HERG potassium channel[J]. J Gen Physiol,2002,120(5):723-737.
[17]Farrelly AM, Ro S, Callaghan BP, et al. Expression and function of KCNH2 (HERG) in the human jejunum[J]. Am. J. Physiol,2003,284(6):883-895.
[18]Camacho J. Ether a go-go potassium channels and cancer[J]. Cancer let,2006,233(2):1-9.
[19]Smith GA, Tsui HW, Newell EW, et al. Functional up-regulation of HERG K+ channels in neoplastic hematopoietic cells[J]. J. Biol. Chem,2002,277(21):18528-18534.
[20]Hancox JC, Witchel HJ, Vanghese A. Alteration of HERG current profile during the cardiac ventricular action potential, following a pore mutation[J]. Biochem Biophys Res Commun. 1998,253(3):719-724.
[21]Witchel HJ, Hancox JC. Familial and acquired long QT syndrome and the cardiac rapid delayed rectifier potassium current[J]. Clin Exp Pharmacol Physiol,2000,27(10):753-766.
[22]Doyle DA, Morais Cabral J, Pfuetzner RA, et al. The structure of the potassium channel: molecular basis of K+ conduction and selectivity [J]. Science,1998,280(5360):69-77.
[23]Zhou Y, Morais-Cabral JH, Kaufman A, et al. Chemistry of ion coordination and hydration revealed by a K+ channel-Fab complex at 2.0 A resolution[J]. Nature,2001,414(6859):43-48.
[24]Trudeau MC, Warmke JW, Ganetzky B, et al. HERG, a human inward rectifier in the voltage-gated potassium channel family[J]. Science,1995,269(5220):92-95.
[25]Wang S, Liu S, Morales MJ, et al. A quantitative analysis of the activation and inactivation kinetics of HERG expressed in Xenopus oocytes[J].J Physiol,1997,502(1):45-60.
[26]Smith PL, Bankrowitz T, Yellen G. The inward rectification mechanism of the HERG cardiac potassium channel[J]. Nature,1996,379(6558):833-836.
[27]Roden DM. Drug-induced prolongation of the QT interval[J]. N Engl J Med,2004,350(10): 1013-1022.
[28]Antzelevitch C. Ionic, molecular, and cellular bases of QT-interval prolongation and torsadede pointes[J]. Europace,2007, (Suppl 4):ⅳ4-ⅳ15.
[29]Dessertenne F. La tachycardie ventriculaire a deux foyers opposes variables[J]. Arch Mal Coeur,1966,59(2):263-272.
[30]Keating MT, Sanguinitti MC. Molecular and cellular mechanisms of cardiac arrhythmias[J]. Cell,2001,104(4):569-580.
[31]Darpo B. Spectrum of drugs prolonging QT interval and the incidence of torsades de pointes[J]. Eur Heart J, Suppl.2001,3(suppl K):K70-K80.
[32]Roden DM. Clinical practice. Long-QT syndrome[J]. N Engl J Med,2008,358(2):169-76.
[33]Schwartz PJ. The congenital long QT syndromes from genotype to phenotype:clinical implications[J]. J Intern Med,2006,259(1):39-47.
[34]Splawski I, Shen J, Timothy KW, et al. Spectrumof mutations in long QT syndrome genes KVLQT1, HERG, SCN5A, KCNE1 and KCNE2[J]. Circulation,2000,102(10):1178-1185.
[35]Mohler PJ, Schott JJ, Gramolini AO, et al. Ankyrin2B mutation causes type 4 long-QT cardiac arrhythmia and sudden cardiac death[J]. Nature,2003,421(6923):634-639.
[36]Tsuboi M, Antzelevitch C. Cellular basis for electrocardiographic and arrhythmic manifestation of Andersen-Tawil syndrome (LQT7)[J]. Heart Rhythm,2006,3(3):328-335.
[37]Shimizu W. The long QT syndrome:therapeutic implications of a genetic diagnosis[J]. Cardiovasc Res,2005,67(3):347-356.
[38]Ye B, Tester DJ, Vatta M, et al. Molecular and functional characterization of novel cav3-encoded caveolin-3 mutations in congenital long QT syndrome, (abst AB1-1)[J]. Heart Rhythm,2006,3(Suppl):Sl.
[39]Domingo AM, Kaku T, Tester DJ, et al. Sodium channel b4 subunit mutation causes congenital long QT syndrome, (abst AB16-6)[J]. Heart Rhythm,2006,3(Suppl):S34.
[40]Zhao JT, Hill AP, Varghese A, et al. Not all hERG pore domain mutations have a severe phenotype:G584S has an inactivation gating defect with mild phenotype compared to G572S, which has a dominant negative trafficking defect and a severe phenotype[J]. J Cardior Electrophysiol,2009; 20(8):923-30.
[41]Mathews DR, Mcnutt B, Okerholm R, et al. Torsades de pointes occurring in association with terfenadine use[J]. JAMA,1991,266(17):2375-2376.
[42]Moss AJ, Zareba W, Kaufman ES, et al. Increased risk of arrhythmic events in long QT syndrome with mutations in the pore region of the human Ether-a-go-go related gene potassium channel[J]. Circulation,2002,105(7):794-799.
[43]Simons FE, Kesselman MS, Giddins NG, et al. Astemizole-induced torsade de pointes[J]. Lancet,1988,10(8611):624.
[44]Delisle BP, Anson BD, Rajamani S, et al. Biology of cardiac an'hythmias:ion channel protein trafficking. Circ Res.2004; 94(11):1418-1428.
[45]Raschi E, Vasina V, Poluzzi E, et al. hERG K+ channel target and antitarget strategies in drug development[J]. Pharmacol Res,2008,57(3):181-195.
[46]Cavero I, Yan GX, Lux R, et al. Safety pharmacology and prolongation of the QT interval[J]. J Electrocardiol,2007,40(1):S58-S61.
[47]Chen J, Zou A, Splawski I, et al. Long QT syndrome-associatedmutations in the Per-Arut-Sim (PAS) domain of HERG potassium channels accelerate channel deactivation[J]. J Biol Chem, 1999,274(15):10113-10118
[48]Nakajima T, Furukawa T, Hiraoka M. Voltage-shift of the current activation in HERG S4 mutation (R534C) in LQT2[J]. Cardiovasc Res,1999,44(2):283-293.
[49]Lees-Miller JP, Duan Y, Teng GQ, et al. Novel gain-of-function mechanism in K+ channel-related long-QT syndrome:alteredgating and selectivity in the HERG1 N629D mutant[J]. Circ Res,2000,86(5):507-513.
[50]Hsueh CH, Chen WP, Lin JL, et al. Functional studies on three novel HCNH2 mutations in Taiwan:Identification of distinct mechanisms of channel defect and dissociation between glycosylation defect and assembly defect[J]. Biochem Biophys Res Commun.2008,373(4): 572-578.
[51]Aydar E, Palmer C. Functional characterization of the C-terminus of the human ether-a-go-go-related gene K+ channel (HERG) [J]. J Physiol,2001,534(1):1-14.
[52]Nademanee K. Genotype-Phenotype Relationship in the Long QT Syndrome[J]. J Am Coll Cardiol,2009,54(22):2063-2064.
[53]Shimizu W, Moss AJ, Wilde AM, et al. Genotype-phenotype aspects of type 2 long QT syndrome[J]. J Am Coll Cardiol,2009,54(22):2052-2062.
[54]Zhou Z, Gong Q, January CT. Correction of defective protein trafficking of a mutant HERG potassium channel in human long QT syndrome:Pharmacological and temperature effects[J]. J Biol Chem,1999,274(44):31123-31126.
[55]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1 (hERG) current by a class 2 (trafficking-deficient) mechanism[J]. Circulation,2006,113(3):365-373.
[56]McPate MJ, Zhang H, Adeniran I, et al. Comparative effects of the short QT N588K mutation at 37 degrees C on hERG K+ channel current during ventricular, Purkinje fibre and atrial action potentials:an action potential clamp study[J]. J Physiol Pharmacol.,2009,60(1): 23-41.
[57]Morita H, Wu J, Zipes DP:The QT syndromes:Long and short[J]. Lancet,2008,372(9640): 750-763.
[58]January CT, Riddle JM. Early after depolarizations:mechanism of induction and block. A role for L-type Ca2+ current[J]. Circ Res,1989,62:563-571.
[59]Lee KS. Ibutilide, a new compound with potent class III antiarrhythmic activity, activates slow inward Na+ current in guinea pig ventricular cells[J]. J Pharmacol Exp Ther,1992, 262(1):99-108.
[60]Busch AE, Malloy K, Groh WJ, et al. The novel class III antiarrhythmic NE-10064 and NE-10133 inhibit IKs channels expressed in Xenopus oocytes and IKs in guinea pig cardiac myocytes[J]. Biochem Biophys Res Commun.1994,202(1):265-270.
[61]Sakaguchi T, Itoh H, Ding WG, et al. Hydroxyzine, a first generation H1-receptor antagonist, inhibits human ether-a-go-go-related gene (HERG) current and causes syncope in a patient with the HERG mutation[J]. J Pharmacol Sci,2008,108(4):462-471
[62]Van der Heyden MA, Smits ME, Vos MA. Drugs and trafficking of ion channels:A new pro-arrhythmic threat on the horizon[J]? Br J Pharmacol,2008,153(3):406-409.
[63]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K+ channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun.,2010, 394(3):536-541.
[64]Gongadze N, Kezeli T, Antelava N. Prolong QT interval and "torsades de pointes" associated with different group of drugs[J]. Georgian Med News,2007, (153):45-49.
[65]KamiyaK, NiwaR, Morishima M, et al. Molecular determinants of hERG channel block by terfenadine and cisapride[J]. J Pharmacol Sci,2008,108(3):301-307.
[66]Park SJ, Kim KS, Kim EJ. Blockade of HERG K+ channel by an antihistamine drug brompheniramine requires the channel binding within the S6 residue Y652 and F656[J]. Appl. Toxicol,2008,28(2):104-111.
[67]Tang Q, Li ZQ, Li W, et al. The 5-HT2 antagonist ketanserin is an open channel blocker of human cardiac ether-a-go-go-related gene (hERG) potassium channels[J]. Bri J Pharmacol, 2008,155(3):365-373.
[68]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K+ channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun.2010, 394(3):536-541.
[69]Duncan RS, McPate MJ, Ridley JM, et al. Inhibition of the HERG potassium channel by the tricyclic antidepressant doxepin[J]. Biochem Pharmacol,2007,74(3):425-437.
[70]Rajamani S, Shryock JC, Belardinelli L. Rapid kinetic interactions of ranolazine with HERG Kl current[J]. J Cardiovasc Pharmacol,2008,51(6):581.
[71]Charpentier F, Merot J, Loussouarn G, et al. Delayed rectifier K+ currents and cardiac repolarization[J]. J Mol Cell Cardio,2010,48(1):37-44.
[72]Thomas D, Kiehn J, Katus HA, et al. Defective protein trafficking in hERG-associated hereditary long QT syndrome (LQT2):Molecular mechanisms and restoration of intracellular protein processing[J]. Cardiovasc Res,2003,60(2):235-241.
[73]Wang L, Dennis AT, Trieu P, et al. Intracellular potassium stabilizes human ether-a-go-go-related gene channels for export from endoplasmic reticulum[J]. Mol Pharmacol,2009,75(4):927-937.
[74]Ficker E, Dennis AT, Wang L, et al. Role of cytosolic chaperones Hsp70 and Hsp90 in maturation of the cardiac potassium channel hERG[J]. Circ Res,2003,92(12):e87-e100.
[75]Gong Q, Jones MA, Zhou Z:Mechanisms of pharmacological rescue of trafficking-defective hERG mutant channels in human long QT syndrome[J]. J Biol Chem,2006,281(7): 4069-4074.
[76]Walker VE, Atanasiu R, Lam H, et al. Co-chaperone FKBP38 promotes hERG trafficking[J]. J Biol Chem,2007,282(32):23509-23516.
[77]Nanduri J, Bergson P, Wang N, et al. Hypoxia inhibits maturation and trafficking of hERG K+ channel protein:Role of Hsp90 and ROS[J]. Biochem Biophys Res Commun.2009,388(2): 212-216.
[78]Roti EC, Myers CD, Ayers RA, et al. Interactions with GM130 during hERG ion channel trafficking. Disruption by type 2 congenital long QT syndrome mutations[J]. J Biol Chem, 2002,277(49):47779-47785.
[79]Ficker E, Kuryshev YA, Dennis AT, et al. Mechanisms of arsenic-induced prolongation of cardiac repolarization[J]. Mol. Pharmacol,2004,66(1):33-44.
[80]Kuryshev YA, Ficker E, Wang L, et al. Pentamidine-induced long QT syndrome and block of hERG trafficking[J]. J Pharmacol Exp Ther,2005,312(1):316-323.
[81]Wang L, Wible BA, Wan X. et al. Cardiac glycosides as novel inhibitors of human Ether-a-go-go-related gene channel trafficking[J]. J. Pharmacol. Exp. Ther,2007,320(2): 525-534.
[82]Guo J, Massaeli H, Li W, et al. Identification of IKr and its trafficking disruption induced by probucol in cultured neonatal rat cardiomyocytes[J]. J. Pharmacol. Exp. Ther,2007,321(3): 911-920.
[83]Rajamani S, Eckhardt LL, Valdivia CR, et al. Drug-induced long QT syndrome:hERG K+ channel block and disruption of protein trafficking by fluoxetine and norfluoxetine[J]. Br. J. Pharmacol,2006,149(5):481-489.
[84]Wible BA, Hawryluk P, Ficker E, et al. HERG-Lite:a novel comprehensive high-throughput screen for drug-induced hERG risk[J]. J. Pharmacol. Toxicol. Methods,2006,52(1):136-145.
[85]Takemasa H, Nagatomo T, Abe H, et al. Coexistence of hERG current blockand disruption of protein trafficking in ketoconazole-induced long QT syndrome[J]. Br J Pharmacol,2008, 153(3):439-447.
[86]Scherer D, Hassel D, Bloehs R, et al:Selective nor-adrenaline reuptake inhibitor atomoxetine directly blocks hERG currents[J]. Br J Pharmacol,2009,156(2):226-236.
[87]Sun H, Liu X, Xiong Q, et al:Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking[J]. J Biol Chem,2006,281(9):5877-5884.
[88]Staudacher I, Schweize PA, Katus HA, et al. hERG:Protein trafficking and potential for therapy and drug side effects[J]. Curr Opin Drug Discov Devel,2010,13(1):23-30.
[89]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1 (hERG) current by a class 2 (trafficking-deficient) mechanism[J]. Circulation,2006; 113(3):365-373.
[90]Radhakrishnan K, Hescheler J, Schneider T. Heat shock proteins and ion channels.functional interactions and therapeutic consequences[J]. Curr Pharm Biotechnol,2010,11(2):175-179.
[91]Gong Q, Jones MA, Zhou Z. Mechanisms of pharmacological rescue of trafficking-defective hERG mutant channels in human long QT syndrome[J]. J. Biol. Chem,2006,281(7): 4069-4074.
[92]Roti, EC, Myers CD, Ayers RA, et al. Interaction with GM130 during HERG ion channel trafficking Disruption by LQT2 mutations[J]. J. Biol. Chem,2002,277(49):47779-47785.
[93]Kagan A, Melman YF, Krumerman A, et al.14-3-3 amplifies and prolongs adrenergic stimulation of HERG K+ channel activity[J]. EMBO J,2002,21(8):1889-1898.
[94]Delisle BP, Underkofler HA, Moungey BM, et al. Small GTPase determinants for the Golgi processing and plasmalemmal expression of human ether-a-go-go related (hERG) K+ channels[J]. J Biol Chem,2009,284(5):2844-2853.
[95]Hieronymus H, Lamb J, Ross KN, et al. Gene expression signature-based chemical genomic prediction identifies a novel class of HSP90 pathway modulators[J]. Cancer Cell,2006,10(4): 321-330.
[96]Sun H, Liu X, Xiong Q, et al. Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking[J]. J. Biol. Chem,2006,281(9):5877-5884.
[97]Isaacs JS, Xu W and Neckers L. Heat shock protein 90 as a molecular target for cancer therapeutics[J]. Cancer Cell,2003,3(3):213-217.
[98]Zhu J, Chen Z, Lallemand-Breitenbach V, et al. How acute promyelocytic leukemia revived arsenic[J]. Nat Rev Cancer,2002,2(9):705-713.
[99]Ohnishi K, Yoshida H, Shigeno K, et al. Prolongation of the QT interval and ventricular tachycardia in patients treated with arsenic trioxide for acute promyelocytic leukemia[J]. Ann. Intern. Med,2000,133(11):881-885.
[100]Drolet B, Simard C, Roden DM. Unusual effects of a QT prolonging drug, arsenic trioxide, on cardiac potassium currents[J]. Circulation,2004,109(1):26-29.
[101]Kuryshev YA, Wang L, Wible BA, et al. Antimony-based antileishmanial compounds prolong the cardiac action potential by an increase in cardiac calcium currents[J]. Mol. Pharmacol,2006,69(4):1216-1225.
[102]Cordes JS, Sun S, Lloyd DB, et al. Pentamidine reduces hERG expression to prolong the QT interval[J]. Br. J. Pharmacol,2005,145(1):15-23.
[103]Zhao XL, Gu DF, Qi ZP, et al. Comparative effects of sophocarpine and sophoridine on hERG K+channel[J]. Eur J Pharmacol,2009,607(1-3):15-22.
[104]Thomas D, Bloehs R, Koschny R, et al. Doxazosin induces apoptosis of cells expressing hERG potassium channels[J]. Eur J Pharmacol,2008,579(1-3):98-103.
[105]Obers S, Staudacher I, Ficker E, et al. Multiple mechanisms of hERG liability:K(+) current inhibition, disruption of protein trafficking, and apoptosis induced by amoxapine[J]. Naunyn-Schmied Arch Pharmacol,2010,13. [Epub ahead of print]
[106]Wang H, Zhang Y, Cao L, et al. HERG K+ channel, a regulator of tumor cell apoptosis and proliferation[J]. Cancer Res,2002,62(17):4843-4848.
[107]Makkar RR, Fromm BS, Steinman RT, et al. Female gender as a risk factor for torsades de pointes associated with cardiovascular drugs[J]. JAMA,1993,270(21):2590-2597.
[108]Zareba W, Moss AJ, Locati EH, et al.Modulating effects of age and gender on the clinical course of long QT syndrome by genotype[J]. J Am Coll Cardiol,2003,42(1): 103-109.
[109]Rautaharju PM, Zhou SH, Wong S, et al. Sex differences in the evolution of the electrocardiographic QT interval with age[J]. Can J Cardiol,1992,8(7):690-695.
[110]Arya A. Gender-related differences in ventricular repolarization:beyond gonadal steroids[J]. J Cardiovasc Electrophysiol,2005,16(5):525-527.
[111]Liu T, Choi BR, Drici MD, et al. Sex modulates the arrhythmogenic substrate in prepubertal rabbit hearts with Long QT 2. [J] J Cardiovasc Electrophysiol,2005,16(5): 516-524.
[112]Gordon E, Panaghie G, Deng L, et al. A KCNE2 mutation in a patient with cardiac' arrhythmia induced by auditory stimuli and serum electrolyte imbalance[J]. Cardiovasc Res, 2008,77(1):98-106.
[113]Numaguchi H, Johnson JP, Petersen CI,et al. A sensitive mechanism for cation modulation of potassium current[J]. Nat Neurosci,2000,3(5):429-430.
[114]Etheridge SP, Compton SJ, Tristani-Firouzi M, et al. A new oral therapy for long QT syndrome:long-term oral potassium improves repolarization in patients with HERG mutations[J]. J Am Coll Cardiol,2003,42(10):1777-1782.
[115]Darbar D, Harris P, Hardy A, et al. Marked steepening of QT restitution following cardioversion of atrial fibrillation [abstract]. Heart Rhythm,2004,1:S192
[116]McCray R, Ritchie MD, Roden DM, et al. Persistent atrial fibrillation is associated with reduced risk of torsades de pointes in patients with drug-induced long QT syndrome [abstract]. J Am Coll Cardiol,2008,51(8):836-842.
[117]Morissette P, Hreiche R, Turgeon J. Drug-induced long QT syndrome and torsade de pointes[J]. Can J Cardiol,2005,21(10):857-864.
[118]Honig PK, Woosley RL, Zamani K, et al. Changes in the pharmacokinetics and electrocardiographic pharmacodynamics of terfenadine with concomitant administration of erythromycin[J]. Clin Pharmacol Ther,1992,52(3):231-238.
[2]Roden DM. Clinical practice. Long-QT syndrome[J]. N Engl J Med,2008,358(2):169-76.
[3]Keating MT, Sanguinitti MC. Molecular and cellular mechanisms of cardiac afthvthmias[J]. Cell,2001,104:569-580.
[4]Schwartz PJ. The congenital long QT syndromes from genotype to phenotype:clinical implications[J]. J Intern Med,2006,259(1):39-47.
[5]Splawski I, Shen J, Timothy KW, et al. Spectrumof mutations in long QT syndrome genes KVLQT1, HERG, SCN5A, KCNE1 and KCNE2[J]. Circulation,2000,102(1):1178-1185.
[6]Mohler PJ, Schott JJ, Gramolini AO, et al. Ankyrin2B mutation causes type 4 long-QT cardiac arrhythmia and sudden cardiac death[J]. Nature,2003,421(6923):634-639.
[7]Tsuboi M, Antzelevitch C. Cellular basis for electrocardiographic and arrhythmic manifestation of Andersen-Tawil syndrome (LQT7)[J]. Heart Rhythm,2006,3(3):328-335.
[8]Shimizu W. The long QT syndrome:therapeutic implications of a genetic diagnosis[J]. Cardiovasc Res,2005,67(3):347-356.
[9]Ye B, Tester DJ, Vatta M, et al. Molecular and functional characterization of novel cav3-encoded caveolin-3 mutations in congenital long QT syndrome, (abst AB1-1) [J]. Heart Rhythm,2006,3(Suppl):S1.
[10]Domingo AM, Kaku T, Tester DJ, et al. Sodium channel b4 subunit mutation causes congenital long QT syndrome.(abst AB16-6) [J]. Heart Rhyth,2006,3(Suppl):S34.
[11].Roy M, Dumaine R, Brown AM. HERG, a primary human ventricular target of the nonsedating antihistamine terfenadine[J]. Circulation,1996,94(4):817-823.
[12]李翠兰,张莉,胡大一等.85例中国人长QT综合征先证者的临床特征及有关基因突变研究现状[J].中华心律失常学杂志,2004,8(6)：328-334.
[13]Keller DI, Grenier J, Christe G, et al. Characterization of novel KCNH2 mutations in type 2 long QT syndrome manifesting as seizures[J]. Can J Cardiol,2009,25(8):455-462.
[14]Surran ME, Splawski I, Timothy KW, et al. A molecular basis for cardiac arrhythmia:HERG mutations cause long QT syndrome[J]. Cell,1995,80(5):795-803.
[15]Sanguinetti MC, Jiang C, Curran ME, et al. A mechanistic link between an inhefited and an acquired cardiac arrhythmia:HERG encodes the IKr potassium channel [J]. Cell,1995,81(2): 299-307.
[16]Yasuda S, Hiramatsu SI, Odashiro K, et al. A family of hereditary long QT syndrome caused by Q738X HERG mutation[J]. Int J Cardiol,2009,19. [Epub ahead of print].
[17]Huo J, huang N, Huang C, et al. The G604S-hERG mutation alters the biophysical properties and exerts a dominant-negative effect on expression of hERG channels in HEK293 cells[J]. Pflugers Arch,2008,456(5):917-928.
[18]Zhou ZF, Gong QM, Epstein ML, et al. HERG channel dysfunction in human long QT syndrome Intracellular transport and functional defects[J]. J Biol Chem,1998,273(3): 21061-21066.
[19]Wang L, Dennis AT, Trieu P, et al. Intracellular potassium stabilizes human ether-a-go-go-related gene channels for export from endoplasmic reticulum[J]. Mol Pharmacol,2009,75(4):927-937.
[20]Delisle BP, Anson BD, Rajamani S, et al. Biology of cardiac an'hythmias:ion channel protein traficking[J]. Circ Res,2004,94(11):1418-1428.
[21]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1 (hERG) current by a class 2 (trafficking-deficient) mechanism[J], Circulation,2006,113(3):365-373.
[22]Chen J, Zou A, Splawski I, et al. Long QT syndrome-associatedmutations in the Per-Arut-Sim (PAS) domain of HERG potassium channels accelerate channel deactivation[J]. J Biol Chem,1999,274(15):L0113-L0118
[23]Nakajima T, Furukawa T, Hiraoka M. Voltage-shift of the current activation in HERG S4 mutation (R534C) in LQT2[J]. Cardiovasc Res,1999,44(2):283-293.
[24]Lees-Miller JP, Duan Y, Teng GQ, et al. Novel gain-of-function mechanism in K+ channel-related long-QT syndrome:altered gating and selectivity in the HERG1 N629D mutant[J]. Circ Res,2000,86(5):507-513.
[25]Kupershmidt S, Yang T, Chanthaphaychith S, et al. Defective human ether-a-go-go-related gene trafficking linked to an endoplasmic reticulum retention signal in the C terminus[J]. J Biol Chem,2002,277(30):27442-27448.
[26]Akhavan A, Atanasiu R, Shrier A. Identification of a COOH-terminal segmentinvolved in maturation and stability of human ether-a-go-go-related gene potassium channels[J]. J Biol Chem,2003,278(41):40105-40112.
[27]Zhao JT, Hill AP, Varghese A, et al. Not all hERG pore domain mutations have a severe phenotype:G584S has an inactivation gating defect with mild phenotype compared to G572S, which has a dominant negative trafficking defect and a severe phenotype[J]. J Cardiovasc Electrophydilo,2009,20(8):923-930.
[28]Hsueh CH, Chen WP, Lin JL, et al. Functional studies on three novel HCNH2 mutations in Taiwan:Identification of distinct mechanisms of channel defect and dissociation between glycosylation defect and assembly defect[J]. Biochem Biophys Res Commun,2008,373(4): 572-578.
[29]Nademanee K. Genotype-Phenotype Relationship in the Long QT Syndrome[J]. J Am Coll Cardiol,2009,54:2063-2064.
[30]Shimizu W, Moss AJ, Wilde AAM, et al. Genotype-phenotype aspects of type 2 long QT syndrome[J]. J Am Coll Cardiol,2009,54(2):2052-2062.
[31]Redfern WS, Carlsson L, Davis AS, et al. Relationships between preclinical cardiac electrophysiology, clinical QT interval prolongation and torsade de pointes for a broad range of drugs:evidence for a provisional safety margin in drug development. Cardiovasc Res. 2003; 58(1):32-45.
[32]Thomas D, Kiehn J, Katus HA, et al. Defective protein trafficking in hERG associated hereditary long QT syndrome (LQT2):molecular mechanisms and restoration of intracellular protein processing[J]. Cardiovasc Res,2003,60(2):235-241.
[33]Gong Q, Keeney DR, Robinson JC, et al. Defective assembly and trafficking of mutant HERG channels with C-terminal truncations in long QT syndrome[J]. J Mol Cell Cardiol, 2004,37(6):1225-1233.
[34]Sasano T, Ueda K, Orikabe M, et al. Hiraoka, Novel C-terminus frameshift mutation, 1122fs/147, of HERG in LQT2:additional amino acids generated by frameshift cause accelerated inactivation[J]. J Mol Cell Cardiol,2004,37(6):1205-1211.
[35]Aydar E, Palmer C. Functional characterization of the C-terminus of the human ether-a-go-go-related gene K+ channel (HERG)[J]. J Physiol,2001,534(Ptl):1-14.
[1]Calderone V, Cavero I. Ventricular arrhythmias. A potential risk associated with the use of non-cardiovascular drugs prolonging the QT interval[J]. M inerva Med,2002,93(3):181-197.
[2]Bajanowski T, Rossi L, Biondo B, et al. Prolonged QT interval and sudden infant death--report of two cases[J]. Forensic Sci Int,2001,115(1-2):147-153.
[3]Numaguchi H, Johnson JP, Petersen CI, et al. A sensitive mechanism for cation modulation of potassium current[J]. Nat Neurosci,2000,3(5):429-430.
[4]Gordon E, Panaghie G, Deng L, et al. A KCNE2 mutation in a patient with cardiac arrhythmia induced by auditory stimuli and serum electrolyte imbalance[J]. Cardiovasc Res,2008,77(1): 98-106.
[5]Ayangade-Johnson G, Villafane J. Long QT interval resembling long QT syndrome in a newborn with electrolyte dysbalance[J]. J Ky Med Assoc,2001,99(7):285-287.
[6]Coumel P, Leclercq JF, Lucet V. Possible mechanisms of the arrhythmias in the long QT syndrome[J]. Eur Heart J,1985,6 Suppl D:115-129.
[7]Okeahialam BN, Sani MU. Heart disease in HIV/AIDS. How much is due tocachexia[J]? Afr J Med Med Sci,2006,35(Suppl):99-102.
[8]Hrovatin E, Zardo F, Brieda M, et al. Long QT and torsade de pointes in a patient with acquired human immunodeficiency virus infection in multitherapy with drugs affecting cytochrome P450[J]. Ital Heart J Suppl,2004,5:735-740.
[9]Van der Heyden MA, Smits ME, Vos MA. Drugs and trafficking of ion channels:A new pro-arrhythmic threat on the horizon[J]? Br J Pharmacol,2008,153(3):406-409.
[10]Lehtonen A, Fodstad H, Laitinen-Forsblom P, et al. Further evidence of inherited long QT syndrome gene mutations in antiarrhythmic drug-associated torsades de pointes[J]. Heart Rhythm,2007,4(5):603-607.
[11]Cheng HC, Incardona J. Models of torsades de pointes:effects of FPL64176, DPI201106, dofetilide, and chromanol 293B in isolated rabbit and guinea pig hearts[J]. J Pharmacol Toxicol Methods,2009.60(2):174-184.
[12]Drici MD, Barhanin J. Cardiac K+ channels and drug-acquired long QT syndrome[J]. Therapie,2000,55(1):185-93.
[13]Su Z, Chen J, Ruth L. et al. Block of hERG channel by ziprasidone:Biophysical properties and molecular determinants[J]. Biochem pharmacol,2006,71(3):278-286.
[14]Park SJ, Kim KS, Kim EJ. Blockade of HERG K+ channel by an antihistamine drug brompheniramine requires the channel binding within the S6 residue Y652 and F656 [J]. Appl. Toxicol,2008,28(2):104-111.
[15]Ray WA, Murray KT, Meredith S, et al. Oral erythromycin and the risk of sudden death from cardiac causes[J]. N Engl J Med,2004,351(11):1089-1096.
[16]Huang BH, Wu CH, Hsia CP, et al. Azithromycin-induced torsade de pointes[J].Pacing Clin Electro physiol,2007,30(2):1579-1582.
[17]Kuryshev YA, Ficker E, Wang L, et al. Pentamidine-induced long QT syndrome and block of hERG trafficking[J]. J Pharmacol Exp Ther,2005,312(1):316-323.
[18]Paakkari I. Cardiotoxicity of new antihistamines and cisapride[J].Toxicol Lett,2002,127(1-3): 279-284.
[19]Zhou Z, Vorperian VR, Gong Q, et al. Block of HERG potassium channels by the antihistamine astemizole and its metabolites desmethylastemizole and norastemizol[J]. J Cardiovasc Electrophysiol,1999,10(6):836-843.
[20]Gongadze N, Kezeli T, Antelava N. Prolong QT interval and "torsades de pointes" associated with different group of drugs[J]. Georgian Med News,2007,153:45-49.
[21]Kamiya K, Niwa R, Morishima M, et al. Molecular determinants of hERG channel block by terfenadine and cisapride[J]. J Pharmacol Sci,2008,108(3):1-8.
[22]Morissette P, Hreiche R, Turgeon J. Drug-induced long QT syndrome and torsade de pointes[J]. Can J Cardiol,2005,21(10):857-864.
[23]Honig PK, Woosley RL, Zamani K, et al. Changes in the pharmacokinetics andelectrocardiographic pharmacodynamics of terfenadine with concomitant administration of erythromycin[J]. Clin Pharmacol Ther,1992,52(3):231-238.
[24]Patmore L, Fraser S, Mair D, et al. Effects of sparfloxacin, grepafloxacin, moxi-floxacin, and ciprofloxacin on cardiac action potential duration[J]. Eur J Pharmacol,2000,406(3):449-452.
[25]Saarnivaara L, Klemola UM, Lindgren L, et al. QT interval of the ECG, heart rate and arterial pressure using propofol, methohexital or midazolam for induction of anaesthesia[J]. Acta Anaesthesiol. Scand,1990,34(4):276-281.
[26]Cremer OL, Moons KG, Bouman EA, et al. Long-term propofol infusion and cardiac failure in adult head-injured patients[J]. Lancet,2001,357(9250):117-118.
[27]Ernest D, French C. Propofol infusion syndrome-report of an adult fatality[J]. Anaesth Intensive Care,2003,31(3):316-319.
[28]Forbes RB, Morton GH. Ventricular fibrillation in a patient with unsuspected mitral valve prolapse and a prolonged Q-T interval[J]. Can. Anaesth. Soc. J,1979,26(5):424-427.
[29]Kies SJ, Pabelick CM, Hurley HA, et al. Anesthesia for patients with congenital long QT syndrome[J]. Anesthesiology,2005,102(1):204-210
[30]Kleinsasser A, Kuenszberg E, Loeckinger A, et al. Sevoflurane, but not propofol, significantly prolongs the Q-T interval[J]. Anesth. Analg,2000,90(1):25-27
[31]Whyte SD, Booker PD, Buckley DG. The effects of propofol and sevoflurane on the QT interval and transmural dispersion of repolarization in children[J]. Anesth Analg,2005,100(1): 71-77.
[32]Paventi S, Santevecchi A, Ranieri R. Effects of sevoflurane versus propofol on QT interval[J]. Minerva. Anestesiol,2001,67(9):637-640.
[33]Kleinsasser A, Loeckinger A, Lindner KH, et al. Reversing sevoflurane-associated QTc prolongation by changing to propofol[J]. Anaesthesia,2001,56(3):248-250.
[34]Yamada M, Hatakeyama N, Malykhina AP, et al. The effects of sevoflurane and propofol onQT interval and heterologously expressed human ether-a-go-go related gene currents inXenopus oocytes[J]. Anesth. Analg,2006,102(1):98-103.
[35]Wang L, Wible BA, Wan X, et al. Cardiac glycosides as novel inhibitors of human ether-a-go-go-related gene channel trafficking[J]. J. Pharmacol Exp Ther,2007,320(2): 525-534.
[36]Takemasa H, Nagatomo T, Abe H, et al. Coexistence of hERG current block and disruption of protein trafficking in ketoconazole-induced long QT syndrome[J]. Br J Pharmacol,2008,153(3)：439-447.
[37]Kamiya K, Niwa R, Mitcheson JS, et al. Molecular determinants of HERG channel block[J]. Mol Pharmacol,2006,69(5):1709-1716.
[38]Kikuchi K, Nagatomo T, Abe H, et al. Blockade of HERG cardiac K+ current by antifungal drug miconazole[J]. Br J Pharmacol,2005,144,840-848.
[39]International conference on Harmonization. S7B:the nonclinical evaluation of the potential for delayed ventricular repolarization (QTinterval prolongation) by humane pharmaccuticals. 2005
[40]International conference on Harmonization. E14:the clinical evaluation of QT/QTc interval prolongation and proarrhythmic potential for non-antiarrhythmic drugs.2005,7
[41]国家食品药品监督管理局.[H]GPT3-1《化学药物一般药理学研究技术指导原则》[S],.2005.
[42]Huo J, Huang N, Huang C, et al. The G604S-hERG mutation alters the biophysical properties dominant-negative effect on expression of hERG channels in HEK-293 cells[J]. Pfluegers Archiv,2008,456(5):917-928.
[43]Li BX, Yang BF, Zhou J, et al. Inhibitory effects of berberine on IK1, IK, and HERG channels of cardiac myocytes[J]. Acta Pharmacol Sin,2001,22(2):125-131.
[44]Thomas D, Kiehn J, Katus HA, et al. Defective protein trafficking in hERG-associated hereditary long QT syndrome (LQT2):Molecular mechanisms and restoration of intracellular protein processing[J]. Cardiovasc Res,2003,60(2):235-241.
[45]Wang L, Dennis AT, Trieu P, et al. Intracellular potassium stabilizes human ether-a-go-go-related gene channels for export from endoplasmic reticulum[J]. Mol Pharmacol,2009,75(4):927-937.
[46]Roti EC, Myers CD, Ayers RA, et al. Interactions with GM130 during hERG ion channel trafficking. Disruption by type 2 congenital long QT syndrome mutations[J]. J Biol Chem, 2002,277(49):47779-47785.
[47]Cordes JS, Sun Z, Lloyd DB, et al. Pentamidine reduces HERG expression to prolong the QT interval[J]. Br J Pharmacol,2005,145(1):15-23.
[48]Ficker E, Kuryshev YA, Dennis AT, et al. Mechanisms of arsenic-induced prolongation of cardiac repolarization[J]. Mol Pharmacol,2004,66(1):33-44.
[49]Guo J, Massaeli H, Li W, et al. Identification of IKr and its trafficking disruption induced by probucol in cultured neonatal rat cardiomyocytes[J]. J. Pharmacol. Exp. Ther,2007,321(3): 911-920.
[50]Rajamani S, Eckhardt LL, Valdivia CR, et al. Drug-induced long QT syndrome:hERG K+ channel block and disruption of protein trafficking by fluoxetine and norfluoxetine[J]. Br. J. Pharmacol,2006,149(5):481-489.
[51]Scherer D, Hassel D, Bloehs R, et al:Selective noradrenaline reuptake inhibitor atomoxetine directly blocks hERG currents[J]. Br J Pharmacol,2009,156(2):226-236.
[52]Sun H, Liu X, Xiong Q, et al. Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking[J]. J Biol Chem,2006,281(9):5877-5884.
[53]Thomas D, Bloehs R, Koschny R, et al. Doxazosin induces apoptosis of cells expressing hERG potassium channels[J]. Eur J Pharmacol,2008,579(1-3):98-103.
[54]Obers S, Staudacher I, Ficker E, et al. Multiple mechanisms of hERG liability:K(+) current inhibition, disruption of protein trafficking, and apoptosis induced by amoxapine[J]. Naunyn-Schmied Arch Pharmacol,2010,13. [Epub ahead of print]
[55]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1(hERG) current by a class 2 (trafficking-deficient) mechanism[J]. Circulation,2006,113:365-373.
[56]Staudacher I, Schweize PA, Katus HA, et al. hERG:Protein trafficking and potential for therapy and drug side effects[J]. Current Opin Drug Discov Dev,2010,13(1):23-30.
[57]Hatakeyama N, Sakuraya F, Matsuda N, et al. Pharmacological significance of the blocking action of the intravenous general anesthetic propofol on the slow component of cardiac delayed rectifier K+ current[J]. J Pharmacol Sci,2009,110(3):334-343
[58]Thomas D, Wendt-Nordahl G, Rockl K, et al. High-affinity blockade of human ether-a go-go-related gene human cardiac potassium channels by the novel antiarrhythmic drug BRL-32872[J]. J Pharmacol Exp Ther,2001,297(2):753-761.
[59]张莹,庄心良,李士通等.丙泊酚、硫喷妥钠对大鼠心肌细胞钙、钾通道电流的影响[J].中华麻醉学杂志,2004,24(9)：673-676.
[60]Wang H, Zhang Y, Cao L, et al. HERG K+ channel, a regulator of tumor cell apoptosis and proliferation[J]. Cancer Res,2002,62(17):4843-4848.
[61]Goldenberg I, Moss AJ, Bradley J, et al. Long-QT syndrome after age 40. Circulation.2008, 117(17):2192-2201.
[62]Zeltser D, Justo D, Halkin A, et al. Torsade de pointes due to noncardiac drugs:most patients have easily identifiable risk factors[J]. Medicine,2003,82(4):282-290.
[63]Amin AS, Herfs LJ, Delisle BP, et al. Fever-induced QTc prolongation and ventricular arrhythmias in individuals with type 2 congenital long QT syndrome. J Clinical Invest,2008, 18(7):2552-2561.
[64]Ping Y, Kanki H, Drolet B, et al. Allelic variants in long-QT disease genes in patients with drug-associated torsade de points. Circulation,2002,105:1943.
[65]Odening KE, Hyder O, Chaves L, et al. Pharmacogenomics of anesthetic drugs in transgenic LQT1 and LQT2 rabbits reveal genotype-specific differential effects on cardiac repolarization[J]. Am J Physiol Heart Circ Physiol,2008,295(6):H2264-H2272.
[1]Van der Heyden MA, Smits ME, Vos MA. Drugs and trafficking of ion channels:A new pro-arrhythmic threat on the horizon[J]? Br J Pharmacol,2008,153(3):406-409.
[2]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K(+) channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun.,2010, 394(3):536-541.
[3]Gongadze N, Kezeli T, Antelava N. Prolong QT interval and "torsades de pointes" associated with different group of drugs[J]. Georgian Med News,2007, (153):45-49.
[4]Sanguinetti MC, Tristani FM. hERG potassium channels and cardiac arrhythmia[J]. Nature, 2006,440(7083):463-469.
[5]Fernandez D, Ghanta A, Kauffman GW, et al. Physicochemical features of the HERG channel drug binding site[J]. J Biol Chem,2004,279(11):10120-10127.
[6]Zhi Su, Jun Chen, Ruth L, et al. Block of hERG channel by ziprasidone:Biophysical properties and molecular determinants[J]. Biochem Pharmacol,2006,71(3):278-286.
[7]Tang Q, Li ZQ, Li W, et al. The 5-HT2 antagonist ketanserin is an open channel blocker of human cardiac ether-a-go-go-related gene (hERG) potassium channels[J]. Bri J Pharmacol, 2008,155(3):365-373.
[8]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K+ channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun,2010,4: [Epub ahead of print]
[9]Duncan RS, McPate MJ, Ridley JM, et al. Inhibition of the HERG potassium channel by the tricyclic antidepressant doxepin. biochem pharm[J].2007,74(3):425-437.
[10]Rajamani S, Shryock JC, Belardinelli L. Rapid kinetic interactions of ranolazine with HERG K+ current[J]. J Cardiovasc Pharmacol,2008,51(6):581.
[11]Thomas D, Bloehs R, Koschny R, et al. Doxazosin induces apoptosis of cells Expressing hERG K+ channels[J]. Eur J Pharmacol,2008,579(1-3):98-103.
[12]Kim KS, Kim EJ, Lee HA, et al. Effect of sibutramine HCl on cardiac hERG K+ channel[J]. Mol Cell Biochem,2009,320(1-2):125-131.
[13]Witchel HJ, Dempsey CE, Sessions RB, et al. The low-potency, voltage-dependent HERG blocker propafenone-molecular determinants and drug trapping[J]. Mol Pharmacol,2004, 66(5):1201-1212.
[14]Mitcheson JS, Chen J, Lin M, et al. A structural basis for drug-induced long QT syndrome[J]. Proc Natl Acad Sci U S.2000,97(22):12329-12333.
[15]Sanchez-Chapula JA, Ferrer T, Navarro-Polanco RA, et al. Voltage-dependent profile of human ether-a-go-go-related gene channel block is influenced by a single residue in the S6 transmembrane domain[J]. Mol Pharmacol,2003,63(5):1051-1058.
[16]Thomas D, Hammeding BC,Wu K. et al. Inhibition of cardiac HERG currents by the DNA topoisomerase Ⅱ inhibitor amsacrine:mode of action[J]. Br J Phannacol,2004,142(3): 485494.
[17]Thomas D, Wimmer AB, Wu K, et al. Inhibition of human ether-ago-go-related gene potassium channels by alpha 1-adrenoceptor antagonists prazosin, doxazosin, and terazasin[J]. Naunyn Schmiedebergs Arch Pharmacol,2004,369(5):462-472.
[18]Sanchez-Chapula JA, Navan-Polataeo RA, Sanguinetti MC. Block of wild-type and inactivation--deficient human ether-a-go-go-mlmed gene K+ channels by halofantrine[J]. Naunyn Schmiedebergs Arch Pharmacol,2004,370(6):484-491.
[19]Viskin S. Long QT syndromes and torsade de pointes[J]. Lancet,1999,354 (9190): 1625-1633.
[20]Kikuchl K, Nagatomo T, Abe H, et al. Blockade of HERG cardiac K+ current by antifungal drug miconzole[J]. Br J Pharmacol,2005,144(6):840-848.
[21]Lees-Miller JP, Dean Y, Teng GQ, et al. Moleclllar determinant of higt-affinity dofetilide binding to HERGl expressed in Xenopus occytes:involvement of S6 sites[J]. Phannacol,2000, 57(2):367-374.
[22]Perry M, de Groot MJ, Helliwell R, et al. Structural determinants of HERG channel block by clofilium and ibutilide[J]. Mol Pbarmacol,2004,66(2):240-249.
[23]Recanatini M, Cavalli A, Masetti M. Modeling HERG and its interactions with drugs:recent advances in light of current potassium channel simulations[J]. Chem. Med. Chem.2008,3(4): 523-535.
[24]Aronov AM. Ligand structural aspects of hERG channel blockade[J]. Curr Top Med Chem. 2008,8(13):1113-1127.
[1]Sanguinetti MC, Jurkiewicz NK. Two components block of delayed rectifier of cardiac delayed rectifier K+ current.differential sensitivity to block by class III anti-arrhythmic agents[J]. J Gen Physiol,1990,96(1):195-215.
[2]Sanguinetti MC, Jurkiewicz NK. Delayed rectifier outward K+ current is composed of two currents in guinea pig atrial cells[J]. Am J Physiol,1991,260(2):H393-H399.
[3]Liu S, Rasmusson RL, Campbell DL, et al. Activation and inactivation kinetics of an E-4031-sensitive current from single ferret atrial myocytes[J]. Biophys J,1996,70(6): 2704-2715.
[4]Davies MP, An RH, Doevendans P, et al. Developmental changes in ionic channel activity in the embryonic mouse heart[J]. Cir Res,1996,78(1):15-25.
[5]Wang L, Feng ZP, Kondo CS, et al. Developmental changes in the delayed rectifier K+ channels in mouse heart[J]. Circ Res,1996,79(1):79-85.
[6]Wymore RS, Gintant GA, Wymore RT, et al. Tissue and species distribution of mRNA for the IKr-like K+ channel, erg[J]. Circ Res,1997,80(2):261-268.
[7]Follmer CH, Colatsky TJ. Block of delayed rectifier potassium current, Ik, by flecainide and E-4031 in cat ventricular myocytes[J]. Circulation,1990,82(1):289-293.
[8]Cordeiro JM, Spitzer KW, Giles WR. Repolarizing K+ currents in rabbit heart Purkinje cells[J]. J Physiol,1998,508(3):811-823.
[9]Gintant GA. Two components of delayed rectifier current in canine atrium and ventricle. Does IKs play a role in the reverse rate dependence of class III agents[J]? Circ Res,1996,78(1): 26-37.
[10]Wang Z, Fermini B, Nattel S. Rapid and slow components of delayed rectifier current in human atrial myocytes[J]. Cardiov Res,1994,28(10):1540-1546.
[11]Li GR, Feng J, Yue L, et al. Evidence for two components of delayed rectifier K+ current in human ventricular myocytes[J]. Circ Res,1996,78(4):689-696.
[12]Warmke JW, Ganetzky B. A family of potassium channel genes related to eag in Drosophila and mammals[J]. Proc. Natl. Acad. Sci. USA,1994,91(8):3438-3442.
[13]Sanguinetti MC, Jiang C, Curran ME, et al. A mechanistic link between an inherited and an acquired cardiac arrhythmia:HERG encodes the IKr potassium channel[J]. Cell,1995,81(2): 299-307.
[14]Trudeau MC, Warmke JW, Ganetzky B, et al. HERG, a human inward rectifier in the voltage-gated potassium channel family[J]. Science,1995,269(5220):92-95.
[15]Morais Cabral JH, Lee A, Cohen SL, et al. Crystal structure and functional analysis of the HERG potassium channel N terminus:a eukaryotic PAS domain[J]. Cell,1998,95(5): 649-655.
[16]Liu J, Zhang M, Jiang M, et al. Structural and functional role of the extracellular S5-P linker in the HERG potassium channel[J]. J Gen Physiol,2002,120(5):723-737.
[17]Farrelly AM, Ro S, Callaghan BP, et al. Expression and function of KCNH2 (HERG) in the human jejunum[J]. Am. J. Physiol,2003,284(6):883-895.
[18]Camacho J. Ether a go-go potassium channels and cancer[J]. Cancer let,2006,233(2):1-9.
[19]Smith GA, Tsui HW, Newell EW, et al. Functional up-regulation of HERG K+ channels in neoplastic hematopoietic cells[J]. J. Biol. Chem,2002,277(21):18528-18534.
[20]Hancox JC, Witchel HJ, Vanghese A. Alteration of HERG current profile during the cardiac ventricular action potential, following a pore mutation[J]. Biochem Biophys Res Commun. 1998,253(3):719-724.
[21]Witchel HJ, Hancox JC. Familial and acquired long QT syndrome and the cardiac rapid delayed rectifier potassium current[J]. Clin Exp Pharmacol Physiol,2000,27(10):753-766.
[22]Doyle DA, Morais Cabral J, Pfuetzner RA, et al. The structure of the potassium channel: molecular basis of K+ conduction and selectivity [J]. Science,1998,280(5360):69-77.
[23]Zhou Y, Morais-Cabral JH, Kaufman A, et al. Chemistry of ion coordination and hydration revealed by a K+ channel-Fab complex at 2.0 A resolution[J]. Nature,2001,414(6859):43-48.
[24]Trudeau MC, Warmke JW, Ganetzky B, et al. HERG, a human inward rectifier in the voltage-gated potassium channel family[J]. Science,1995,269(5220):92-95.
[25]Wang S, Liu S, Morales MJ, et al. A quantitative analysis of the activation and inactivation kinetics of HERG expressed in Xenopus oocytes[J].J Physiol,1997,502(1):45-60.
[26]Smith PL, Bankrowitz T, Yellen G. The inward rectification mechanism of the HERG cardiac potassium channel[J]. Nature,1996,379(6558):833-836.
[27]Roden DM. Drug-induced prolongation of the QT interval[J]. N Engl J Med,2004,350(10): 1013-1022.
[28]Antzelevitch C. Ionic, molecular, and cellular bases of QT-interval prolongation and torsadede pointes[J]. Europace,2007, (Suppl 4):ⅳ4-ⅳ15.
[29]Dessertenne F. La tachycardie ventriculaire a deux foyers opposes variables[J]. Arch Mal Coeur,1966,59(2):263-272.
[30]Keating MT, Sanguinitti MC. Molecular and cellular mechanisms of cardiac arrhythmias[J]. Cell,2001,104(4):569-580.
[31]Darpo B. Spectrum of drugs prolonging QT interval and the incidence of torsades de pointes[J]. Eur Heart J, Suppl.2001,3(suppl K):K70-K80.
[32]Roden DM. Clinical practice. Long-QT syndrome[J]. N Engl J Med,2008,358(2):169-76.
[33]Schwartz PJ. The congenital long QT syndromes from genotype to phenotype:clinical implications[J]. J Intern Med,2006,259(1):39-47.
[34]Splawski I, Shen J, Timothy KW, et al. Spectrumof mutations in long QT syndrome genes KVLQT1, HERG, SCN5A, KCNE1 and KCNE2[J]. Circulation,2000,102(10):1178-1185.
[35]Mohler PJ, Schott JJ, Gramolini AO, et al. Ankyrin2B mutation causes type 4 long-QT cardiac arrhythmia and sudden cardiac death[J]. Nature,2003,421(6923):634-639.
[36]Tsuboi M, Antzelevitch C. Cellular basis for electrocardiographic and arrhythmic manifestation of Andersen-Tawil syndrome (LQT7)[J]. Heart Rhythm,2006,3(3):328-335.
[37]Shimizu W. The long QT syndrome:therapeutic implications of a genetic diagnosis[J]. Cardiovasc Res,2005,67(3):347-356.
[38]Ye B, Tester DJ, Vatta M, et al. Molecular and functional characterization of novel cav3-encoded caveolin-3 mutations in congenital long QT syndrome, (abst AB1-1)[J]. Heart Rhythm,2006,3(Suppl):Sl.
[39]Domingo AM, Kaku T, Tester DJ, et al. Sodium channel b4 subunit mutation causes congenital long QT syndrome, (abst AB16-6)[J]. Heart Rhythm,2006,3(Suppl):S34.
[40]Zhao JT, Hill AP, Varghese A, et al. Not all hERG pore domain mutations have a severe phenotype:G584S has an inactivation gating defect with mild phenotype compared to G572S, which has a dominant negative trafficking defect and a severe phenotype[J]. J Cardior Electrophysiol,2009; 20(8):923-30.
[41]Mathews DR, Mcnutt B, Okerholm R, et al. Torsades de pointes occurring in association with terfenadine use[J]. JAMA,1991,266(17):2375-2376.
[42]Moss AJ, Zareba W, Kaufman ES, et al. Increased risk of arrhythmic events in long QT syndrome with mutations in the pore region of the human Ether-a-go-go related gene potassium channel[J]. Circulation,2002,105(7):794-799.
[43]Simons FE, Kesselman MS, Giddins NG, et al. Astemizole-induced torsade de pointes[J]. Lancet,1988,10(8611):624.
[44]Delisle BP, Anson BD, Rajamani S, et al. Biology of cardiac an'hythmias:ion channel protein trafficking. Circ Res.2004; 94(11):1418-1428.
[45]Raschi E, Vasina V, Poluzzi E, et al. hERG K+ channel target and antitarget strategies in drug development[J]. Pharmacol Res,2008,57(3):181-195.
[46]Cavero I, Yan GX, Lux R, et al. Safety pharmacology and prolongation of the QT interval[J]. J Electrocardiol,2007,40(1):S58-S61.
[47]Chen J, Zou A, Splawski I, et al. Long QT syndrome-associatedmutations in the Per-Arut-Sim (PAS) domain of HERG potassium channels accelerate channel deactivation[J]. J Biol Chem, 1999,274(15):10113-10118
[48]Nakajima T, Furukawa T, Hiraoka M. Voltage-shift of the current activation in HERG S4 mutation (R534C) in LQT2[J]. Cardiovasc Res,1999,44(2):283-293.
[49]Lees-Miller JP, Duan Y, Teng GQ, et al. Novel gain-of-function mechanism in K+ channel-related long-QT syndrome:alteredgating and selectivity in the HERG1 N629D mutant[J]. Circ Res,2000,86(5):507-513.
[50]Hsueh CH, Chen WP, Lin JL, et al. Functional studies on three novel HCNH2 mutations in Taiwan:Identification of distinct mechanisms of channel defect and dissociation between glycosylation defect and assembly defect[J]. Biochem Biophys Res Commun.2008,373(4): 572-578.
[51]Aydar E, Palmer C. Functional characterization of the C-terminus of the human ether-a-go-go-related gene K+ channel (HERG) [J]. J Physiol,2001,534(1):1-14.
[52]Nademanee K. Genotype-Phenotype Relationship in the Long QT Syndrome[J]. J Am Coll Cardiol,2009,54(22):2063-2064.
[53]Shimizu W, Moss AJ, Wilde AM, et al. Genotype-phenotype aspects of type 2 long QT syndrome[J]. J Am Coll Cardiol,2009,54(22):2052-2062.
[54]Zhou Z, Gong Q, January CT. Correction of defective protein trafficking of a mutant HERG potassium channel in human long QT syndrome:Pharmacological and temperature effects[J]. J Biol Chem,1999,274(44):31123-31126.
[55]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1 (hERG) current by a class 2 (trafficking-deficient) mechanism[J]. Circulation,2006,113(3):365-373.
[56]McPate MJ, Zhang H, Adeniran I, et al. Comparative effects of the short QT N588K mutation at 37 degrees C on hERG K+ channel current during ventricular, Purkinje fibre and atrial action potentials:an action potential clamp study[J]. J Physiol Pharmacol.,2009,60(1): 23-41.
[57]Morita H, Wu J, Zipes DP:The QT syndromes:Long and short[J]. Lancet,2008,372(9640): 750-763.
[58]January CT, Riddle JM. Early after depolarizations:mechanism of induction and block. A role for L-type Ca2+ current[J]. Circ Res,1989,62:563-571.
[59]Lee KS. Ibutilide, a new compound with potent class III antiarrhythmic activity, activates slow inward Na+ current in guinea pig ventricular cells[J]. J Pharmacol Exp Ther,1992, 262(1):99-108.
[60]Busch AE, Malloy K, Groh WJ, et al. The novel class III antiarrhythmic NE-10064 and NE-10133 inhibit IKs channels expressed in Xenopus oocytes and IKs in guinea pig cardiac myocytes[J]. Biochem Biophys Res Commun.1994,202(1):265-270.
[61]Sakaguchi T, Itoh H, Ding WG, et al. Hydroxyzine, a first generation H1-receptor antagonist, inhibits human ether-a-go-go-related gene (HERG) current and causes syncope in a patient with the HERG mutation[J]. J Pharmacol Sci,2008,108(4):462-471
[62]Van der Heyden MA, Smits ME, Vos MA. Drugs and trafficking of ion channels:A new pro-arrhythmic threat on the horizon[J]? Br J Pharmacol,2008,153(3):406-409.
[63]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K+ channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun.,2010, 394(3):536-541.
[64]Gongadze N, Kezeli T, Antelava N. Prolong QT interval and "torsades de pointes" associated with different group of drugs[J]. Georgian Med News,2007, (153):45-49.
[65]KamiyaK, NiwaR, Morishima M, et al. Molecular determinants of hERG channel block by terfenadine and cisapride[J]. J Pharmacol Sci,2008,108(3):301-307.
[66]Park SJ, Kim KS, Kim EJ. Blockade of HERG K+ channel by an antihistamine drug brompheniramine requires the channel binding within the S6 residue Y652 and F656[J]. Appl. Toxicol,2008,28(2):104-111.
[67]Tang Q, Li ZQ, Li W, et al. The 5-HT2 antagonist ketanserin is an open channel blocker of human cardiac ether-a-go-go-related gene (hERG) potassium channels[J]. Bri J Pharmacol, 2008,155(3):365-373.
[68]Hong HK, Park MH, Lee BH, et al. Block of the human ether-a-go-go-related gene (hERG) K+ channel by the antidepressant desipramine[J]. Biochem Biophys Res Commun.2010, 394(3):536-541.
[69]Duncan RS, McPate MJ, Ridley JM, et al. Inhibition of the HERG potassium channel by the tricyclic antidepressant doxepin[J]. Biochem Pharmacol,2007,74(3):425-437.
[70]Rajamani S, Shryock JC, Belardinelli L. Rapid kinetic interactions of ranolazine with HERG Kl current[J]. J Cardiovasc Pharmacol,2008,51(6):581.
[71]Charpentier F, Merot J, Loussouarn G, et al. Delayed rectifier K+ currents and cardiac repolarization[J]. J Mol Cell Cardio,2010,48(1):37-44.
[72]Thomas D, Kiehn J, Katus HA, et al. Defective protein trafficking in hERG-associated hereditary long QT syndrome (LQT2):Molecular mechanisms and restoration of intracellular protein processing[J]. Cardiovasc Res,2003,60(2):235-241.
[73]Wang L, Dennis AT, Trieu P, et al. Intracellular potassium stabilizes human ether-a-go-go-related gene channels for export from endoplasmic reticulum[J]. Mol Pharmacol,2009,75(4):927-937.
[74]Ficker E, Dennis AT, Wang L, et al. Role of cytosolic chaperones Hsp70 and Hsp90 in maturation of the cardiac potassium channel hERG[J]. Circ Res,2003,92(12):e87-e100.
[75]Gong Q, Jones MA, Zhou Z:Mechanisms of pharmacological rescue of trafficking-defective hERG mutant channels in human long QT syndrome[J]. J Biol Chem,2006,281(7): 4069-4074.
[76]Walker VE, Atanasiu R, Lam H, et al. Co-chaperone FKBP38 promotes hERG trafficking[J]. J Biol Chem,2007,282(32):23509-23516.
[77]Nanduri J, Bergson P, Wang N, et al. Hypoxia inhibits maturation and trafficking of hERG K+ channel protein:Role of Hsp90 and ROS[J]. Biochem Biophys Res Commun.2009,388(2): 212-216.
[78]Roti EC, Myers CD, Ayers RA, et al. Interactions with GM130 during hERG ion channel trafficking. Disruption by type 2 congenital long QT syndrome mutations[J]. J Biol Chem, 2002,277(49):47779-47785.
[79]Ficker E, Kuryshev YA, Dennis AT, et al. Mechanisms of arsenic-induced prolongation of cardiac repolarization[J]. Mol. Pharmacol,2004,66(1):33-44.
[80]Kuryshev YA, Ficker E, Wang L, et al. Pentamidine-induced long QT syndrome and block of hERG trafficking[J]. J Pharmacol Exp Ther,2005,312(1):316-323.
[81]Wang L, Wible BA, Wan X. et al. Cardiac glycosides as novel inhibitors of human Ether-a-go-go-related gene channel trafficking[J]. J. Pharmacol. Exp. Ther,2007,320(2): 525-534.
[82]Guo J, Massaeli H, Li W, et al. Identification of IKr and its trafficking disruption induced by probucol in cultured neonatal rat cardiomyocytes[J]. J. Pharmacol. Exp. Ther,2007,321(3): 911-920.
[83]Rajamani S, Eckhardt LL, Valdivia CR, et al. Drug-induced long QT syndrome:hERG K+ channel block and disruption of protein trafficking by fluoxetine and norfluoxetine[J]. Br. J. Pharmacol,2006,149(5):481-489.
[84]Wible BA, Hawryluk P, Ficker E, et al. HERG-Lite:a novel comprehensive high-throughput screen for drug-induced hERG risk[J]. J. Pharmacol. Toxicol. Methods,2006,52(1):136-145.
[85]Takemasa H, Nagatomo T, Abe H, et al. Coexistence of hERG current blockand disruption of protein trafficking in ketoconazole-induced long QT syndrome[J]. Br J Pharmacol,2008, 153(3):439-447.
[86]Scherer D, Hassel D, Bloehs R, et al:Selective nor-adrenaline reuptake inhibitor atomoxetine directly blocks hERG currents[J]. Br J Pharmacol,2009,156(2):226-236.
[87]Sun H, Liu X, Xiong Q, et al:Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking[J]. J Biol Chem,2006,281(9):5877-5884.
[88]Staudacher I, Schweize PA, Katus HA, et al. hERG:Protein trafficking and potential for therapy and drug side effects[J]. Curr Opin Drug Discov Devel,2010,13(1):23-30.
[89]Anderson CL, Delisle BP, Anson BD, et al. Most LQT2 mutations reduce Kv11.1 (hERG) current by a class 2 (trafficking-deficient) mechanism[J]. Circulation,2006; 113(3):365-373.
[90]Radhakrishnan K, Hescheler J, Schneider T. Heat shock proteins and ion channels.functional interactions and therapeutic consequences[J]. Curr Pharm Biotechnol,2010,11(2):175-179.
[91]Gong Q, Jones MA, Zhou Z. Mechanisms of pharmacological rescue of trafficking-defective hERG mutant channels in human long QT syndrome[J]. J. Biol. Chem,2006,281(7): 4069-4074.
[92]Roti, EC, Myers CD, Ayers RA, et al. Interaction with GM130 during HERG ion channel trafficking Disruption by LQT2 mutations[J]. J. Biol. Chem,2002,277(49):47779-47785.
[93]Kagan A, Melman YF, Krumerman A, et al.14-3-3 amplifies and prolongs adrenergic stimulation of HERG K+ channel activity[J]. EMBO J,2002,21(8):1889-1898.
[94]Delisle BP, Underkofler HA, Moungey BM, et al. Small GTPase determinants for the Golgi processing and plasmalemmal expression of human ether-a-go-go related (hERG) K+ channels[J]. J Biol Chem,2009,284(5):2844-2853.
[95]Hieronymus H, Lamb J, Ross KN, et al. Gene expression signature-based chemical genomic prediction identifies a novel class of HSP90 pathway modulators[J]. Cancer Cell,2006,10(4): 321-330.
[96]Sun H, Liu X, Xiong Q, et al. Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking[J]. J. Biol. Chem,2006,281(9):5877-5884.
[97]Isaacs JS, Xu W and Neckers L. Heat shock protein 90 as a molecular target for cancer therapeutics[J]. Cancer Cell,2003,3(3):213-217.
[98]Zhu J, Chen Z, Lallemand-Breitenbach V, et al. How acute promyelocytic leukemia revived arsenic[J]. Nat Rev Cancer,2002,2(9):705-713.
[99]Ohnishi K, Yoshida H, Shigeno K, et al. Prolongation of the QT interval and ventricular tachycardia in patients treated with arsenic trioxide for acute promyelocytic leukemia[J]. Ann. Intern. Med,2000,133(11):881-885.
[100]Drolet B, Simard C, Roden DM. Unusual effects of a QT prolonging drug, arsenic trioxide, on cardiac potassium currents[J]. Circulation,2004,109(1):26-29.
[101]Kuryshev YA, Wang L, Wible BA, et al. Antimony-based antileishmanial compounds prolong the cardiac action potential by an increase in cardiac calcium currents[J]. Mol. Pharmacol,2006,69(4):1216-1225.
[102]Cordes JS, Sun S, Lloyd DB, et al. Pentamidine reduces hERG expression to prolong the QT interval[J]. Br. J. Pharmacol,2005,145(1):15-23.
[103]Zhao XL, Gu DF, Qi ZP, et al. Comparative effects of sophocarpine and sophoridine on hERG K+channel[J]. Eur J Pharmacol,2009,607(1-3):15-22.
[104]Thomas D, Bloehs R, Koschny R, et al. Doxazosin induces apoptosis of cells expressing hERG potassium channels[J]. Eur J Pharmacol,2008,579(1-3):98-103.
[105]Obers S, Staudacher I, Ficker E, et al. Multiple mechanisms of hERG liability:K(+) current inhibition, disruption of protein trafficking, and apoptosis induced by amoxapine[J]. Naunyn-Schmied Arch Pharmacol,2010,13. [Epub ahead of print]
[106]Wang H, Zhang Y, Cao L, et al. HERG K+ channel, a regulator of tumor cell apoptosis and proliferation[J]. Cancer Res,2002,62(17):4843-4848.
[107]Makkar RR, Fromm BS, Steinman RT, et al. Female gender as a risk factor for torsades de pointes associated with cardiovascular drugs[J]. JAMA,1993,270(21):2590-2597.
[108]Zareba W, Moss AJ, Locati EH, et al.Modulating effects of age and gender on the clinical course of long QT syndrome by genotype[J]. J Am Coll Cardiol,2003,42(1): 103-109.
[109]Rautaharju PM, Zhou SH, Wong S, et al. Sex differences in the evolution of the electrocardiographic QT interval with age[J]. Can J Cardiol,1992,8(7):690-695.
[110]Arya A. Gender-related differences in ventricular repolarization:beyond gonadal steroids[J]. J Cardiovasc Electrophysiol,2005,16(5):525-527.
[111]Liu T, Choi BR, Drici MD, et al. Sex modulates the arrhythmogenic substrate in prepubertal rabbit hearts with Long QT 2. [J] J Cardiovasc Electrophysiol,2005,16(5): 516-524.
[112]Gordon E, Panaghie G, Deng L, et al. A KCNE2 mutation in a patient with cardiac' arrhythmia induced by auditory stimuli and serum electrolyte imbalance[J]. Cardiovasc Res, 2008,77(1):98-106.
[113]Numaguchi H, Johnson JP, Petersen CI,et al. A sensitive mechanism for cation modulation of potassium current[J]. Nat Neurosci,2000,3(5):429-430.
[114]Etheridge SP, Compton SJ, Tristani-Firouzi M, et al. A new oral therapy for long QT syndrome:long-term oral potassium improves repolarization in patients with HERG mutations[J]. J Am Coll Cardiol,2003,42(10):1777-1782.
[115]Darbar D, Harris P, Hardy A, et al. Marked steepening of QT restitution following cardioversion of atrial fibrillation [abstract]. Heart Rhythm,2004,1:S192
[116]McCray R, Ritchie MD, Roden DM, et al. Persistent atrial fibrillation is associated with reduced risk of torsades de pointes in patients with drug-induced long QT syndrome [abstract]. J Am Coll Cardiol,2008,51(8):836-842.
[117]Morissette P, Hreiche R, Turgeon J. Drug-induced long QT syndrome and torsade de pointes[J]. Can J Cardiol,2005,21(10):857-864.
[118]Honig PK, Woosley RL, Zamani K, et al. Changes in the pharmacokinetics and electrocardiographic pharmacodynamics of terfenadine with concomitant administration of erythromycin[J]. Clin Pharmacol Ther,1992,52(3):231-238.