CAJ | 학술논문

利用全脑缺血模型,采用免疫印迹和免疫沉淀方法,探讨N-甲基-D-天冬氨酸受体和L-型电压门控钙通道拮抗剂对细胞色素c从线粒体中的释放和Bcl-2的表达变化影响.缺血/复灌后24 h,线粒体中细胞色素c明显降低而胞浆中细胞色素c的成分相应增加.Bcl-2的表达呈时间依赖性,其表达在缺血/复灌后6 h达到最大.在所有样品中,线粒体呼吸链蛋白细胞色素氧化酶没有变化,表明线粒体的制备方法是可靠的.线粒体中Bcl-2的表达减少和细胞色素c的释放可以被NMDA受体拮抗剂氯胺酮和L-型电压门控钙通道拮抗剂尼氟地平抑制.结果表明,N-甲基-D-天冬氨酸受体和L-型电压门控钙通道可能介导了脑缺血后细胞色素c从线粒体中的释放和Bcl-2的上调表达.缺血诱导的细胞色素c释放具有损伤作用而Bcl-2的上调表达则对脑缺血具有一定的保护作用.
이용전뇌결혈모형,채용면역인적화면역침정방법,탐토N-갑기-D-천동안산수체화L-형전압문공개통도길항제대세포색소c종선립체중적석방화Bcl-2적표체변화영향.결혈/복관후24 h,선립체중세포색소c명현강저이포장중세포색소c적성분상응증가.Bcl-2적표체정시간의뢰성,기표체재결혈/복관후6 h체도최대.재소유양품중,선립체호흡련단백세포색소양화매몰유변화,표명선립체적제비방법시가고적.선립체중Bcl-2적표체감소화세포색소c적석방가이피NMDA수체길항제록알동화L-형전압문공개통도길항제니불지평억제.결과표명,N-갑기-D-천동안산수체화L-형전압문공개통도가능개도료뇌결혈후세포색소c종선립체중적석방화Bcl-2적상조표체.결혈유도적세포색소c석방구유손상작용이Bcl-2적상조표체칙대뇌결혈구유일정적보호작용.
To evaluate the effects of different antagonists on the release of cytochrome c from mitochondria to cytosol and the expression of Bcl-2 in mitochondria in rat hippocampus after ischemia, we examined Bcl-2 and cytochrome c expression by immunoblotting using 4-vessel occlusion (4-VO) as brain ischemia model. The results showed that after 24 h ischemia/reperfusion (I/R) cytochrome c decreased markedly in mitochondria, which was correspondingly increased in the cytosolic fraction. Bcl-2 expression was time-dependent, reaching its peak level after 6 h I/R. In all those samples, there were no alterations in the subcellular distribution of cytochrome oxidase, a mitochondrial respiratory chain protein. The decreases in Bcl-2 and cytochrome c in mitochondria were restored by pretreatment with non-competitive NMDA receptor antagonist ketamine or L-type voltage-gated Ca2+ channel (L-VGCC) antagonist nifedipine at 20 min prior to ischemia. The results demonstrate that the release of cytochrome c from mitochondria to cytosol and the up-regulation of Bcl-2are possibly mediated by NMDA receptors or L-VGCC following brain ischemia. Cytochrome c release may be injurious while Bcl-2 upregulation may be protective to ischemic hippocampus.