摘要
目的:银杏叶提取物(Extract of Ginkgo Biloba Egb761)是从银杏树叶中提取的具有多种生物活性成分,主要含银杏黄酮苷、银杏内酯及少量白果内酯。据实验研究表明:银杏黄酮苷有提高SOD活性及清除氧自由基的作用,银杏内酯是目前较为典型的血小板激活因子(PAF)拮抗剂,由于上述药理作用,银杏叶标准提取物(Egb761)在减轻组织器官缺血再灌注损伤中起重要作用。本实验研究旨在探索Egb761在肺移植中对供体肺的保护作用,以求延长肺保存时间及加快术后肺功能恢复。
方法:采用三套管大鼠原位左肺移植模型,对照组与实验组各五对,对照组用100ml/kg4℃生理盐水灌注肺,取肺后保存于4℃生理盐水中,2小时后移植于受体,开
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放循环后0.5小时、1 小时各取血标本作血清丙二醛
(Maloudialdekyde Al)A)、谷光甘肽(Glutathione
GSH)测定,1小时后将移植肺取出,分别作肺干湿重比
及肺组织MDA、GSH测定。实验组:手术方法同前,在
供体取肺前半小时经下腔静脉注射银杏叶提取物(金纳
多)0.15mill009,并在灌注液中同样也加人金纳多
10mm。保存2 .J’时后移植,受体在移植前半小时经
尾静脉注射金纳多0.临。移植后开放循环0.5 ,J’
时、1小时各取血标本作血清MDA、GSH测定,1小时
将移植肺取出,分别作肺干湿重比及肺组织MDA、GSR
测定。另取5只正常SD大鼠,手术方法同前,开胸后迅
速取肺、取血标本,分别作血清Nil3A、GSH,肺组织
A413A、GSH浓度测定以及肺组织湿于重比,此数据作为
移植前基础值。实验所得数据都经统计软件SPSS处理。
结果:无缺血时血清MDA、GSH浓度分别为4.539
士0.225nmollml,426.62士3.95*glL;肺组织 MDA、GSR
浓度分别为:0.638土 0.018nmoV吧,32.82土 1.199mglthg;
肺组织湿干重比为:5.54士0.081,上述数据作为移植前基础
值。移植对照组门用药组> 移植后半小时血清MDA、
GSH浓度分别为:6.61士0.409 nmo*l;320.41士9.00 mgth;
2
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移植后一小时血清 MDA、GSR浓度分划为:9.589土OAf7
nmollml; 189.57士9.03m叭;移植后一小时肺组织
A41:)A、GSR浓度分别为:0.936土0.025 nmoVmg;24。902
土1.645二;肺组织湿干重比为:5.927士0.112。与无缺
血组相比血清MDA、GSH,肺组织MDA、GSH以及肺组
织湿干重比均有显著性差异(P<0.01人用药组:移植后半
J时血清MD A、*SB 浓度分别为:5.475土0.295 urn讪*
3的.”士6.0瞰;移植后一小时血清MI>A、GSH浓度
分别为:7.603士0.294 nmoFml; 267.65士7.785 mglL;移植
后一小时肺组织M13A、GSH浓度分别为:0.799士0o34
nmotheg; 28.501土1.7幻 m咖g;肺组织湿于重比为:6.279
上0.09。与无缺血组相比血清All3A、GSH,肺组织MDA、
GSH以及肺组织湿干重比均有显著性差异(P<0.of入与
对照组相比血清MDA、GSH,肺组织MDA、GSH以及肺
组织湿干重比也有显著性差异O吻.0N叼.01人
结论:
1、供体肺在移樟后存在严重的脂质过氧化作用,表现
在血清及肺组织NlllA的升高,GSH的消耗,肺水肿的发
生。
工银杏叶提取物贝gM61)能有效地减轻肺损伤,保护
3
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肺不受氧自由的攻击。表现在血清及肺组织MDA的升高、
GSR的消耗比对照组明显降低。
3、本实验中银杏叶提取物只能部分阻断脂质过氧化,
是肺移植中损伤机制的多方面还是剂量问题,尚待阐明。
4、用药组肺水肿反而明显,其机理尚待研究。
Objective: Ginkgo biloba extract contained several effective components, of which the flavonoid glycosides and terpene lactones act the main pharmacological effect of this drug. Many researches have confirmed that it act as a scavenger of free radical and antagonist of platelet activating factor(PAF), which plays a very important role in the mechanism of ischemic reperfusion injury in lung transplantation. Our study is aim at examining the protective effect of standardized extract of Ginkgo biloba (Egb761 Dr. Willmar Schwabe GMBH &Co. flavonoid
glycosides :3.5mg/ml ; terpene: 0.21mg/ml: Ginkgolic acid<5ppm) on donor lung in lung transplantation in SD rats.
Methods: SD rats orthotopic left lung transplantation model were employed. Group I (n=5): donors received no drug pretreatment and perfused with cold normal saline(4 *C) , after 2 hours of cold ischemia, donor lung was
transplanted to the recipient. Group n (n=5): Donors pretreated with Egb761(0.15ml/100g body weight) 30 minutes before harvest and another dosage of Egb761 (Iml/lOOg body weight) were added to the perfusate, and the recipients also pretreated with Egb761(0.15ml/100g body weight) 30 minutes before operation. Malondialdehyde (MDA) and Glutathione (GSH) were determined in blood serum 0.5 and 1 hour after reperfusion and in lung tissue after 1 hour of reperfusion, lung wet/dry ratio was measure after 1 hour of reperfusion. We take another 5 rats , MDA and GSH in blood serum ^ lung tissue and lung wet/dry ratio were determined after anesthesia as performed in Group I and II. This data served a base line of rats before ischemia.
Results: 30 minutes after reperfusion the blood serum
MDA concentration in Group I is higher than in pro-ischemia(PO.001) and in Group II (PO.001); GSH in Group I is lower than in pro-ischemia (PO.001) and in Group II (PO.001). This change became much worse after 1 hour of reperfusion. In lung tissue, MDA and GSH concentration are significant difference in Group I (MDA: PO.001, GSH: PO.001) and in Group H (MDA: PO.001, GSH: P=0.003) after 1 hour of reperfusion. We also observed a significant difference between two Groups(MDA: PO.001; GSH: P=0.01). Lung water gain(lung wet/dry ratio) is higher in Group I (P=0.001) and in Group II (PO.001) as compared with in pro-ischemia, and between the two Groups, Group II is higher than in Group I (P=0.001).
Conclusions:
1): Lipid peroxidation is one of the mechanism in lung ischemic reperfusion injury in lung transplantation.
2): The protective effect of Egb761 is by inhibiting on lipid peroxidation.
3): Egb761 partially reduced donor lung ischemic reperfusion injury in our study.
4): The mechanism of Egb761 on lung edema is unknown and need to be investigated.
引文
1、张煜,黄芸,焦清平等。银杏叶提取物预防离体大鼠心肌缺血再灌注损伤。中国临床药学杂志。2000:Vol 9 No3 163-165
2、韩得恩,张新晨,田素礼等.银杏叶提取物对无心跳供肝热缺血损伤保护作用的实验研究.中华器官移植杂志 2001:Vol.22 No.1 48-51
3、张煜,黄芸.银杏叶提取物预防心肌缺血再灌注损伤的研究进展.国外医学.心血管疾病分册.2000:Vol.27 No1:29-31
4、邓云坤,余志豪,喻田等.银杏叶提取物心停跳液对心肌保护效果.中华麻醉学杂志 1999:Vol 19 No 2:116117
5、陈维洲,张培智.银杏叶提取物的药理和临床研究进展(上).中国新药与临床杂志 1999:Vol 18 No 5:315-317
6、陈维洲,张培智.银杏叶提取物的药理和临床研究进展
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