预处理对老年鼠脑缺血bcl-2表达及细胞凋亡的影响

目的观察缺血预处理对脑缺血再灌注损伤的保护作用。方法将SD老年大鼠分为2组缺血预处理10min再灌注24h再次缺血24h组(PI)及单纯缺血对照组(CI),采用尼龙线栓法制作大鼠局灶性脑缺血模型,通过免疫组化染色技术及原位末端标记技术(TUNEL)检测大鼠大脑皮质bcl-2蛋白的表达和细胞凋亡情况。结果PI组较CI组缺血皮层bcl-2蛋白表达明显增强(P<0.01)。PI组缺血皮层凋亡细胞较CI组明显减少(P<0.05)。结论缺血预处理使缺血脑组织bcl-2蛋白表达增强,抑制凋亡细胞产生,说明缺血预处理对再次脑缺血有保护作用。

Effects of ischemia preconditioning on bcl-2 protein expression and cell apoptosis in elderly rats after focal cerebral ischemia injuries

Objective To observe the protective effects of cerebral ischemia preconditioning on cerebral ischemic injury caused by subsequent middle cerebral artery occlusion (MCAO) in SD rats. Methods Male Sprage-Dawley rats were divided into two groups. The first group(PI): 10 minutes of ischemic precondition, 24 hours of reperfusion, and then 24 hours of occlusion of the right middle cerebral artery (MCA); the second group (CI): occlusions of MCAO were performed by inserting nylon suture into the internal carotid artery. Immunohistostaining and TUNEL staining technique were used to examine bcl-2 protein expression and neuronal apoptosis on ischemic cortex. Results In the PI group positive bcl-2 protein expression in the ischemic cortex was more notable than that in the CI group (P<0.01); Cell apoptosis in the ischemic cortex of CI group is much more than that of PI group (P<0.05). Conclusions Ischemic preconditioning increases expression of bcl-2 protein and inhibits cell apoptosis, so it may induce ischemic brain tolerance and has protective effects.