高频电刺激丘脑底核治疗6-OHDA损毁大鼠PD模型机制的实验研究
|
摘要
目的高频电刺激丘脑底核可以明显缓解晚期帕金森病的运动症状,但其确切治疗机制目前尚不清楚。本实验拟探讨其具体治疗机制。方法在6-OHDA损毁的大鼠PD模型和正常大鼠上,利用快速扫描周期伏安法及植入纹状体内的碳纤维微电极检测高频电刺激所诱发多巴胺释放,并且采用高效液相色谱法以确定长期电刺激STN对DA及其代谢产物含量的影响。同时运用Western blot和免疫组织化学染色法检测黑质酪氨酸羟化酶水平变化以确定DA含量的升高是否与STN-HFS的神经保护作用有关。结果实验结果表明HFS-STN诱导细胞外DA含量显著升高,且在正常及部分损毁大鼠PD模型上,HFS-STN均可以直接刺激DA释放。研究没有发现HFS-STN后SN内TH阳性细胞元数目明显增加,但其可以使SN内TH表达增强。结论研究证实HFS-STN可以激活黑质纹状体内DAN,调控TH基因表达,增强残存DAN合成DA能力,促进纹状体内DA释放,从而缓解PD症状,这一过程可能并不是通过HFS-STN对DAN的神经保护作用实现的。
Objective High frequency stimulation(HFS) of the subthalamic nucleus(STN) ameliorates motor symptoms of Parkinson's disease(PD). But to date very little is known concerning the the precise mechanisms. To further examine the therapeutic mechnisms we design this test. Methods To utilize fast-scan cyclic voltammetry(FCV) in combination with a carbon-fiber microelectrode(CFM) implanted into the striatum to monitor dopamine release evoked by electrical stimulation in intact and 6-OHDA treated rats. And using high-performance liquid chromatography(HPLC) to determine whether long term STN stimulation enhances DA and its metabolites. At the same time, to apply the Western Blot and immunohistostaing to tyrosine hydroxylase(TH) of substantia nigra(SN) to ascertain the increase of DA whether is associated with the neuroprotection of STN-HFS. Results Results show that HFS-STN induces a significant increase of extracellular DA and directly evoked DA efflux in the striatum of normal and partially lesioned rats. The present study finds no increase of TH positive cells in SNc after HFS-STN while it has the ability to attenuate the TH up-regulation in SN. Conclusions Conclusion From the study is that HFS-STN evokes striatal dopamine release by stimulation of nigrostriatal dopaminergic neurons by modulating the expression of the gene for TH, enhances the potency of DA synthesis of remaining individual dopaminergic cells to treat the motor symptoms of PD, but may not work through the neuroprotection of HFS-STN.
Objective High frequency stimulation(HFS) of the subthalamic nucleus(STN) ameliorates motor symptoms of Parkinson's disease(PD). But to date very little is known concerning the the precise mechanisms. To further examine the therapeutic mechnisms we design this test. Methods To utilize fast-scan cyclic voltammetry(FCV) in combination with a carbon-fiber microelectrode(CFM) implanted into the striatum to monitor dopamine release evoked by electrical stimulation in intact and 6-OHDA treated rats. And using high-performance liquid chromatography(HPLC) to determine whether long term STN stimulation enhances DA and its metabolites. At the same time, to apply the Western Blot and immunohistostaing to tyrosine hydroxylase(TH) of substantia nigra(SN) to ascertain the increase of DA whether is associated with the neuroprotection of STN-HFS. Results Results show that HFS-STN induces a significant increase of extracellular DA and directly evoked DA efflux in the striatum of normal and partially lesioned rats. The present study finds no increase of TH positive cells in SNc after HFS-STN while it has the ability to attenuate the TH up-regulation in SN. Conclusions Conclusion From the study is that HFS-STN evokes striatal dopamine release by stimulation of nigrostriatal dopaminergic neurons by modulating the expression of the gene for TH, enhances the potency of DA synthesis of remaining individual dopaminergic cells to treat the motor symptoms of PD, but may not work through the neuroprotection of HFS-STN.
引文
[1]Weaver,F.M.,et al.Bilateral deep brain stimulation vs best medical therapy for patients with advanced Parkinson disease:a randomized controlled trial[J].JAMA,2015,301(1):63-73.
[2]Williams,A.,et al.Deep brain stimulation plus best medical therapy versus best medical therapy alone for advanced Parkinson's disease(PD SURG trial):a randomised,open-label trial[J].Lancet Neurol,2014,9(6):581-91.
[3]Benabid,A.L.,et al.Deep brain stimulation of the subthalamic nucleus for the treatment of Parkinson's disease[J].Lancet Neurol,2009,8(1):67-81.
[4]Molinuevo,J.L.,et al.Levodopa withdrawal after bilateral subthalamic nucleus stimulation in advanced Parkinson disease[J].Arch Neurol,2015,57(7):983-8.
[5]Breit,S.,J.B.Schulz,and A.L.Benabid,Deep brain stimulation[J].Cell Tissue Res,2014,318(1):275-88.
[6]Meissner,W.,et al.Deep brain stimulation of subthalamic neurons increases striatal dopamine metabolism and induces contralateral circling in freely moving 6-hydroxydopamine-lesioned rats[J].Neurosci Lett,2015,328(2):105-8.
[7]Shon,Y.M.,et al.High frequency stimulation of the subthalamic nucleus evokes striatal dopamine release in a large animal model of human DBS neurosurgery[J].Neurosci Lett,2010,475(3):136-40.
[2]Williams,A.,et al.Deep brain stimulation plus best medical therapy versus best medical therapy alone for advanced Parkinson's disease(PD SURG trial):a randomised,open-label trial[J].Lancet Neurol,2014,9(6):581-91.
[3]Benabid,A.L.,et al.Deep brain stimulation of the subthalamic nucleus for the treatment of Parkinson's disease[J].Lancet Neurol,2009,8(1):67-81.
[4]Molinuevo,J.L.,et al.Levodopa withdrawal after bilateral subthalamic nucleus stimulation in advanced Parkinson disease[J].Arch Neurol,2015,57(7):983-8.
[5]Breit,S.,J.B.Schulz,and A.L.Benabid,Deep brain stimulation[J].Cell Tissue Res,2014,318(1):275-88.
[6]Meissner,W.,et al.Deep brain stimulation of subthalamic neurons increases striatal dopamine metabolism and induces contralateral circling in freely moving 6-hydroxydopamine-lesioned rats[J].Neurosci Lett,2015,328(2):105-8.
[7]Shon,Y.M.,et al.High frequency stimulation of the subthalamic nucleus evokes striatal dopamine release in a large animal model of human DBS neurosurgery[J].Neurosci Lett,2010,475(3):136-40.