“调神通络”针法对脑缺血大鼠大脑皮层蛋白激酶Cγ、蛋白激酶Cδ表达的影响

目的:探讨局灶脑缺血再灌注大鼠蛋白激酶C(PKC)γ、PKCδ表达在缺血性脑损害中的动态变化规律以及针刺的干预机制。方法:Wistar大鼠随机分为针刺组、模型组和正常组。前两组再分为缺血再灌注4h、12h、24h、72h组。采用线栓法制备大鼠局灶脑缺血再灌注模型。电针针刺大鼠右侧顶中线和顶旁线,频率2Hz/15Hz,强度1mA。运用免疫组化方法观察缺血侧大脑皮层PKCγ、PKCδ吸光度值。结果:PKCγ、PKCδ在正常组呈基础水平表达,模型组与正常组相比PKCγ、PKCδ表达明显升高(P<0.01)。针刺组与模型组相比,相应时间点PKCγ、PKCδ吸光度值减弱(P<0.01,P<0.05)。结论:脑缺血再灌注损伤后PKCγ、PKCδ的异常表达与神经元坏死、凋亡有密切的联系。针刺能明显减少PKCγ、PKCδ蛋白表达及神经元凋亡,对脑缺血神经元起着保护作用。

Effect of Electroacupuncture on Cerebral PKC Isozyme Expression Levels in Cerebral Ischemia-reperfusion Rats

Objective To observe the effect of electroacupuncture(EA) of "Dingzhongxian"(MS 5) and "Dingpang-xian"(MS 8) on the expression of cerebral protein kinase C(PKC) isozymes in local cerebral ischemia reperfusion injury(CI/RI) rats so as to explore its underlying mechanism in protecting ischemic brain tissue.Methods Seventy-two Wistar rats were randomized into normal control(n=8),CI/RI model(model,n=32),and EA(n=32) groups.The later two groups were further divided into 4,12,24 and 72 h subgroups,respectively,with 8 rats in each.CI/RI model was established by occlusion of the middle cerebral artery under anesthesia and reperfusion for 4,12,24 and 72 h,respectively.EA(1 mA,2 Hz/15 Hz) was applied to "Dingzhongxian"(MS 5) and "Dingpangxian"(MS 8) for 10 min every time,and once again every 12 h after modeling.The expression of PKCγ and PKCδ in the ischemic cortex tissue was detected using immunohistochemistry.TdT-mediated dUTP Nick-End Labeling was used to detect neuronal apoptosis of the local ischemic cerebral cortex.Results In comparison with the normal group,the expression levels of cerebral PKCγ and PKCδ proteins as well as the number of the apoptotic neurons at time-points of 4,12,24 and 72 h after modeling were increased apparently in the model group(P<0.01);while compared with the model group,cerebral PKCγ and PKCδ protein expressions and the apoptotic neuronal number were decreased considerably in the EA group(P<0.01,P<0.05).No significant differences were found among the 4 time-points in the expression levels of PKCγ and PKCδ and apoptotic neuronal number in the model group and EA group(P>0.05).Conclusion EA intervention can effectively down-regulate expressions of cerebral PKCγ,PKCδ proteins and apoptotic neuronal number in cerebral ischemia rats,which may contribute to its effect in protecting the ischemic cerebral tissue.