【摘要】 目的：探讨Ｃａｓｐａｓｅ－３与局灶性脑缺血后神经元凋亡的关系。方法：局灶性脑缺血再灌流大鼠模型，按再灌流时间不同随机分为５组。用半定量ＲＴ－ＰＣＲ观察了脑缺血后不同时程Ｃａｓｐａｓｅ－３ ｍＲＮＡ表达及四肽荧光底物法检测Ｃａｓｐａｓｅ３蛋白酶活性；用ＴＵＮＥＬ方法检测不同时程细胞凋亡。结果：脑缺血２ｈ再灌流２ｈ组Ｃａｓｐａｓｅ－３ ｍＲＮＡ水平即已升高（Ｐ＜０．０５），蛋白酶活性轻度升高，再灌流６ｈ后两者均明显升高（Ｐ＜０．０５）；脑缺血再灌流后不同时程细胞凋亡具有与Ｃａｓｐａｓｅ－３相似的变化趋势。结论：提示脑缺血后细胞凋亡的发生与Ｃａｓｐａｓｅ－３的激活有关。更多还原

【Abstract】 Aim:To observe the role of caspase-3 activation in neuronal apoptosis after middle cerebral artery occlusion in rats. Methods: By using the model of focal cerebral ischemia in Wistar rats, DNA fragmentation,caspase-3 mRNA and enzy- matic activity were measured in the sham-operated group and 2, 6, 18, 24, 48h reperfusion after 2h cerebral ischemia. Results: DNA fragmentation was observed in samples from injuried brain area beginning from 6~18h after and continuing for at least 2d by TUNEL and FCM. Caspase-3 mRNA levels, estimated by semiquantitative RT-PCR, were elevated three-fold by 6h and five-fold by 24 h after reperfusion. Increased caspase-3 enzymatic activity was found in cytosolic extract from ischemic area,but to a lesser extent than caspase-3 mRNA. The changes of caspase-3 enzymatic activity is consistent with DNA frag- mentation. Conclusion: It is suggested that activation of caspase-3 contributes to neuronal apoptosis after middle cerebral artery occlusion.更多还原