大鼠脑缺血再灌注后Smac、XIAP和caspase-9表达及活血通络方的干预作用

目的：探讨大鼠脑缺血再灌注后线粒体通路第二种天冬氨酸特异性半胱氨酸蛋白酶激活物（Smac）、凋亡抑制蛋白（XIAP）和凋亡蛋白酶（caspase）-9的表达变化及活血通络方的干预作用机理。方法：将大鼠随机分成模型组、活血通络组,大脑中动脉栓塞再通法建立脑缺血再灌注模型。大鼠脑缺血再灌注6、12、24和48 h不同时间点进行神经功能评分,用免疫组化法检测Smac、XIAP和caspase-9阳性细胞数。结果：缺血再灌注后6 h模型组神经功能症状积分升高,缺血半暗带皮质内神经元凋亡增多,Smac、XIAP和caspase-9蛋白的表达亦有明显上升,再灌注12 h达高峰（P〈0.05,P〈0.01）,随后出现下降。活血通络方能显著降低神经功能症状积分,减少神经元凋亡,促进XIAP表达,下调Smac和caspase-9表达（P〈0.01,P〈0.05）。结论：脑缺血再灌注后脑组织Smac、XIAP和caspase-9蛋白的表达均明显增加,提示它们可能在脑缺血再灌注损伤中发挥重要作用,活血通络方可能通过促进XIAP并抑制Smac、caspase-9表达保护神经元及神经功能。

Study on the Expression of Smac, XIAP and Caspase-9 in Rats with Cerebral Ischemia/Reperfution and the Interventional Effects of Huoxue Tongluo Recipe

Objective： To explore the expression of Smac, XIAP and caspase-9 on mitochondria pathway induced by cerebral ischemia-reperfusion（FR） as well as the mechanisms of the interventional effect of Huoxue Tongluo recipe. Methods： Rats were randomly divided into modelling group, Huoxue Tonglao group （HXTL group）. The modle of cerebral I/R was induced by middle cerebral artery occlusion（MCAO） and recanalization. Neural function score were evaluated at 6, 12, 24 and 48 hours after cerebral reperfusion. The positive neurons of Smac, XIAP and caspase-9 were detected by immunohistochemistry at different time points after reperfusion. Results： At 6 h after reperfusion, the neural function score markedly upgraded, apoptotic index（AI） and the positive neurons of Smac, XIAP and cas- pase-9 increased significantly in the penumbra of rat cortex, and peaked at 12 h （P〈0.05, P〈0.01）, and then declined. HXTL Recipe could significantly degrade the neural function score, decrease the AI, upregulate the expressions of XIAP and downregulate the Smac, caspase-9 （P〈0.05, P〈0.01）. Conclusions： Smac, XIAP and caspase-9 play important roles in the cerebral I/R injury. Huoxue Tongtuo recipe could protect neurons and the neural function from I/R injury by improving the expression levels of XIAP as well as inhibiting the expression of Smac and caspase-9.