[Involvement of cerebral neuroglobin in electroacupuncture preconditioning-induced protection effect in cerebral ischemia-reperfusion rats].

Objective To observe the effect of electroacupuncture(EA) preconditioning on cerebral ischemia and the role of cerebral neuroglobin(NgB) in EA-induced brain protection in focal cerebral ischemia and reperfusion injury(CI/RI) rats.Methods Male SD rats were randomly assigned to sham control,CI/RI 6 h,CI/RI 24 h and CI/RI 72 h groups(n=6) for observing changes of NgB at different time-points.Additional SD rats were randomly assigned to sham,model,and EA preconditio-ning(EA-PC) groups(n=16) for observing changes of cerebral NgB positive cell counts in the ischemic penumbra region 24 h after reperfusion.EA pre-conditioning was applied to "Baihui"(GV 20) for 30 min,once daily for 5 days before CI/RI.CI/RI model was established by occlusion of the right middle cerebral artery and reperfusion for 6 h,24 h and 72 h respectively.The neurological behavior scores(NBS) of all the rats were evaluated according to Garcia's methods.The cerebral infarct volume was determined by 2,3,5-triphenyltetrazolium chloride(TTC) staining.The number of cerebral NgB positive cells was detected by immunofluorescent staining.Results No infarct loci were found in the sham group.The cerebral infarction volume percentage was significantly higher in the model group than in the EA-PC group(P0.01),while the NBS was significantly lower in the model group than in the EA-PC group(P0.01).The number of cerebral NgB positive cells in the ischemic penumbra was up-regulated 6 h after CI/RI injury,peaked at 24 h and continued at 72 h.Compared with the sham group,the number of cerebral NgB positive cells of the model group was increased significantly,whereas that of the EA-PC group up-regulated further obviously in comparison with the model group(P0.01).Conclusion EA pretreatment has a significant neuroprotective effect on cerebral ischemia-reperfusion,which is closely related to its effect in up-regulating NgB protein expression.