尼卡地平联合异丙酚预处理对沙鼠缺血后再灌注神经细胞凋亡的影响

The effects of nicardipine plus propofol on neural apoptosis in gerbils

目的 探讨尼卡地平联合异丙酚预处理对缺血后再灌注神经细胞凋亡的影响 ,并检测经尼卡地平和异丙酚联合预处理后的沙土鼠脑组织中抑凋亡基因Bcl 2的表达。方法 采用夹闭沙土鼠双侧颈总动脉造成脑缺血模型。 5 0只健康成年沙土鼠随机分成五组 ,每组各 1 0只 :假手术对照组 (A组 ) ;脑缺血对照组 (B组 ) ,全脑缺血 5min后再灌注 72h ;尼卡地平预处理组 (C组 ) ;异丙酚预处理组 (D组 ) ;尼卡地平联合异丙酚预处理组 (E组 )。C、D、E三组缺血前 30min分别静脉给予尼卡地平 0 2mg/kg、腹腔注射异丙酚 1 0 0mg/kg以及两者同时联合处理 ,缺血 5min后分别再灌注 72h。实验终末 ,断头取脑 ,石蜡切片 ,采用DNA末端标记技术 (TUNEL法 )观察各组脑细胞凋亡的变化情况并采用免疫组化染色评定Bcl 2蛋白反应强度。结果 E组的凋亡细胞百分数明显低于其他各组 ,而Bcl 2蛋白免疫反应强度高于其它各组(P <0 0 5 )。结论 短暂性脑缺血再灌注后有细胞凋亡发生 ,脑缺血前经尼卡地平联合异丙酚预处理后 ,能明显减少细胞凋亡的发生 ,此与Bcl 2蛋白表达增强有关。

Objective To investigate the effects of preconditioning with nicardipine and propofol on gerbils neuron apoptosis,and to study the relation between the expression of Bcl 2 protein and protection against ischemic neuronal damage by preconditioning with them.Methods The cerebral ischemia was induced by occlusion of bilateral common carotid arteries.Fifty gerbils were divided randomly into five groups,ten animals each:sham operative control group(group A);ischemic control group(group B)with a 5 min cerebral ischemia and following 72h reperfusion;nicardipine preconditioning group(group C):Nic(0 2mg/kg)was iv 30 min prior to ischemia;propofol preconditioning group(group D):propofol(100mg/kg)was injected into abdominal cavity 30 min prior to ischemia;nicardipine associated propofol preconditioning group(group E):Nic(0 2mg/kg,iv)associated propofol(100mg/kg,injected into abdominal cavity)30 min prior to ischemia.The animals were sacrificed immediately at the end of the experiment.Neural apoptosis was identified by terminal deoxynucleotidyltransferse mediated dUPT biotin nick end labeling(TUNEL)and Paraffin sections of cortex were used for Bcl 2 protein immunohistochemical staining.Results The apoptotic cells percentages in group E were markedly lower than in group A,B,C and D( P <0 05)and Bcl 2 protein immunoreactivity(the intensity of staining)significantly increased compared with that in the other groups( P <0 05).Conclusion Neural apoptosis oppear after transient cerebral ischemia reperfusion.To preconditioning with nicardipine associated propofol can decrease the apoptotic cells percentages potentlyl against ischemia reperfusion brain damage,which is closely related to the expression of Bcl 2 protein. [