树脑缺血后海马线粒体应激与神经元损伤机制研究  

The mechanisms of hippocampal mitochondrial stress and neuronal injury after thrombotic cerebral ischemia in Tree Shrews

作　　者：张颖[1] 李树清[1] 陈静[1] 

机构地区：[1]昆明医学院基础医学院病理生理教研室,云南昆明650031

出　　处：《中风与神经疾病杂志》2007年第2期140-142,共3页Journal of Apoplexy and Nervous Diseases

基　　金：教育部博士点专项基金(No20050678008);云南省自然科学基金资助项目(No2004C0043M);国家自然科学基金资助项目(No30660056)

摘　　要：目的研究光化学诱导树脑缺血后不同时间海马神经元细胞色素C(CytC)表达及caspase mRNA含量的改变;探讨脑缺血时神经元线粒体应激导致海马继发性损伤的分子机制。方法免疫组化法检测树缺血后不同时间缺血侧海马神经元CytC蛋白表达;低温差速离心分离海马脑组织线粒体和细胞质部分,western blot法检测其CytC的含量变化;实时荧光PCR检测海马组织caspase-3及caspase-9 mRNA。结果光化学诱导树脑缺血后,海马神经元CytC于24h时由线粒体释放入胞质,而caspase-3、caspase-9 mRNA显著升高,caspase-3与caspase-9之间具有相关性。结论光化学诱导树脑缺血后,海马神经元线粒体应激,促凋亡蛋白CytC从线粒体释放入胞质,改变了空间分布,启动caspase级联反应,是脑缺血后海马神经元继发性损伤的病理生理机制之一。Objective To explore the changes in expression of cytochrome C protein of hippocampal neurons and the contents of caspase mRNA after thrombotic cerebral ischemia,we will provide a molecular mechanism of mitochondrial stress resulting in the hippocampal neurons secondary injury. Methods The expression of cytochrome C was observed in ischemic lateral hippocampi at different times by immunochemistry. Also, the hippocampus was removed,then mitochondria and cytoplasmic fragment were divided by low temperature centrifugation and the distribution of cytochrome C was assessed through western blot. We used real time fluorescence polymerase chain reaction to evaluate the contents of caspase-3 and caspase-9 mRNA. Results Cytochrome C was released from mitochondria into the cytosol at 24h. The contents of caspase-3 and caspase-9 mRNA increased. There was a positive correlation between caspase-3 and caspase-9. Conclusion After photochemical inducing cerebral ischemia in tree shrews,hipppocampal neuronal mitochondrias begin to stress and proapoptotic protein cytochrome C released from mitochondria into cytoplasm,which trigger caspase cascade reaction. This is one of the pathophysiological mechanism about hippocampal neuronal secondary injury after cerebral ischemia.

关 键 词：脑缺血 海马 线粒体 胞色素C CASPASE 树鼩 

分 类 号：R743.3[医药卫生—神经病学与精神病学]