电针对脑缺血再灌注大鼠脑红蛋白的影响

目的:观察脑缺血再灌注损伤大鼠脑红蛋白(neuroglobin,NgB)的表达以及电针预处理对NgB表达的影响,探索NgB在电针预处理诱导的脑保护效应中的作用。方法:雄性SD大鼠随机分为假手术组、模型组及电针组,每组16只。电针组给予电针刺激"百会",每天30min,持续5d。预处理后采用右侧大脑中动脉阻闭法,缺血120min后行再灌注,制备大鼠局灶性脑缺血再灌注损伤模型。脑缺血再灌后24h进行神经行为学评分,然后检测脑梗死容积,免疫荧光双标法检测NgB表达水平。另一批SD雄性大鼠随机分为假手术组、缺血再灌注6、24、72h组,每组6只,分别通过免疫荧光双标法观察缺血半暗带NgB表达水平的变化。结果:电针预处理后电针组较模型组脑梗死容积百分比明显减低(P<0.01),神经行为学评分及NgB含量明显增加(P<0.01)。脑缺血再灌注后6hNgB表达开始上调,24h为表达高峰(P<0.01),并至少可以持续到72h。结论:电针预处理能显著提高脑缺血再灌注大鼠神经行为学评分,降低脑梗死容积,并可进一步上调缺血半暗带NgB表达,诱导脑缺血耐受,从而减轻脑缺血再灌注损伤。

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(P<0.01),while the NBS was significantly lower in the model group than in the EA-PC group(P<0.01).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(P<0.01).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.