电针诱导神经生长因子透血脑屏障效应及其机制分析

摘要

Objective To observe the effect of electroacupuncture (EA) of "Baihui" (GV 20) and "Yamen" (GV 15) on the permeability of blood-brain barrier for exogenous nerve growth factor (NGF) and its relevance to PKC pathway in cerebral ischemia (CI) rats. Methods Forty-eight SD rats were randomized into sham-operation (sham), model, NGF, EA, NGF+EA, and NGF + H7 + EA groups. CI model was established by repeated occlusion of the bilateral carotid arteries and reperfusion. NGF (10 μg/kg) was administrated by intravenous injection (vena caudalis); while H 7 [1-(5-isoquinolinesulfonyl)-2-mehtylpopera-zine, an inhibitor of protein kinase C (PKC), 1 mg/kg] was given by intraperitoneal injection. EA (100 Hz, 2 mA) was applied to "Baihui" (GV 20) and "Yamen" (GV 15) for 20 min. NGF content in the brain tissue was assayed by enzyme-labeled immunosor-bent assay (ELISA). Results In comparison with sham group, cerebral NGF content had no apparent change in model group ( P>0. 05). Comparison among the abovementioned 6 groups showed that cerebral NGF level in NGF+ EA group was significantly higher than those in sham, model, EA and NGF groups (P<0. 01). No significant differences were found among sham, model, NGF, EA and NGF+ H7 + EA groups and between NGF + EA and NGF + H7 + EA groups in cerebral NGF contents ( P>0. 05). Conclusion EA of GV 20 and GV 15 can raise the permeability of blood-brain barrier for NGF to increase its level in the cerebral tissue in CI rats, favoring the regeneration and repair of nerves, which has no clear relevance to PKC pathway.%目的:观察电针"百会""哑门"诱导外源性神经生长因子(NGF)透过血脑屏障的效应及其促透效应与蛋白激酶C(PKC)信号传导通路的相关性.方法:采用急性反复脑缺血再灌注法制造脑缺血学习记忆障碍大鼠模型,3周后,将动物随机分为模型对照组、NGF组(尾静脉注射NGF)、电针组(电针"百会""哑门")、NGF+电针组(尾静脉注射NGF,同时"百会""哑门"通以电针)、NGF+H7+电针组(尾静脉注射NGF后注射异喹啉磺酰类H7,同时"百会""哑门"通以电针),另设假手术组,每组均8只大鼠.采用ELISA法检测各组大鼠脑组织中NGF含量.结果:NGF组大鼠脑组织中NGF含量与模型对照组比较,差异无统计学意义(P＞0.05);NGF+电针组大鼠脑组织中NGF含量与假手术组、模型对照组、NGF组及电针组比较均明显升高,差异均有统计学意义(P＜0.01);NGF+H7+电针组与NGF+电针组比较,脑组织中NGF含量有下降趋势,但差异不具统计学意义(P＞0.05).结论:"百会""哑门"电针能诱导NGF透过血脑屏障,使大鼠脑组织中NGF含量明显提高,该促透作用与PKC信号通路相关性不明显.