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.