电针对局灶性脑缺血再灌注大鼠神经血管单元的保护作用

Protective Effect of Electroacupuncture Intervention on Neurovascular Unit in Rats with Focal Cerebral Ischemia-reperfusion Injury

目的:观察电针对大脑中动脉缺血再灌注(MCAO/R)模型大鼠神经行为学及脑组织血管内皮生长因子(VEGF)、神经生长相关蛋白-43(GAP-43)、突触囊泡蛋白(SYN)、髓鞘碱性蛋白(MBP)、勿动蛋白A(Nogo-A)表达的影响,探讨电针对MCAO/R模型大鼠神经血管单元的保护作用及其机制。方法:雄性SD大鼠随机分为假手术组、模型组和电针组,每组20只。采用线栓法制作大鼠MCAO/R模型。电针刺激在造模成功90min后进行,针刺双侧"内关""水沟""三阴交"及"百会"穴,留针30min,每天针刺1次,共14d。各组大鼠在7、14d两个时间点各取10只进行神经功能评估并行免疫组化SP法检测缺血脑组织VEGF、GAP-43、SYN、MBP、Nogo-A的表达。结果:模型组出现明显神经功能缺损症状,14d电针组大鼠神经功能恢复明显优于模型组(P<0.05)。与假手术组比较,模型组7、14d缺血组织VEGF、GAP-43、Nogo-A的表达增多,SYN在两个时间点的表达均减少(P<0.01,P<0.05);与模型组比较,电针组7、14d缺血组织VEGF、GAP-43、SYN、MBP阳性表达均增多(P<0.01,P<0.05),Nogo-A的表达减少(P<0.01)。结论:①电针能有效改善局灶性脑缺血再灌注大鼠的神经功能;②电针能通过上调各时间点局灶性脑缺血再灌注大鼠脑组织内VEGF、GAP-43、SYN、MBP的表达,下调Nogo-A的表达,促进血管、神经元、神经胶质细胞的恢复,从而保护脑缺血再灌注大鼠的神经血管单元。

Objective To observe the effect of electroacupuncture （EA） intervention on behavior changes, expression of cerebral vascular endothelial growth factor （VEGF）, nerve growth associated protein-43 （GAP-43）, synaptophysin （SYN）, myelin basic protein （MBP）, neurite outgrowth inhibitor-A （Nogo-A） in cerebral focal ischemia-reperfusion injury （Ol/RI） rats, so as to study its mechanism underlying improvement of ischemic cerebral vascular disease. Methods Sixty male SD rats were randomly divided into sham-operation group, model group and electroacupuncture （EA） group. Cl/RI model was established by occlusion of the middle cerebral artery （MCAO） and reperfusion. EA was applied to bilateral ＂Neiguan＂（PC 6）, ＂Sanyinjiao＂ （SP 6）, ＂Shuigou＇（GV 26） and ＂Baihui＂ （GV 20） for 30 rain, once a day for 14 days. The neurologic deficits were evaluated by Longa 5-grade standard （the higher the score, the severer the neurologic deficit）. The immunoactivity of cerebral VEGF, GAP-43, SYN, MBP （important in the process of myelination of nerves in the nervous system） and Nogo-A （inhibiting axonal re- generation） in the focal ischemic cerebral tissue was detected by immunohistochemistry. Results The Longa＇s score of the model group was significantly increased after MOAO in comparison with the sham-operation group （P〈0.01）. In comparison withthe model group, Longa＇s score of the EA group was evidently lower on day 14 after Cl/RI （P〈0.05）, suggesting an improve- ment of the neurological deficits after EA intervention. In comparison with the sham-operation group, the immunoactivity of cere- bral VEGF, GAP-43 and Nogo-A was significantly upregulated on day 7 and 14 in the model group （P〈0.01）, while that of cere- bral SYN was remarkably down-regulated in the model group on day 7 and 14 after CI/RI （P〈0.05）. Compared with the model group, cerebral VEGF, GAP-43, SYN and MBP expression levels were considerably upregulated on day 7 and 14 following CI/RI in the EA group （P〈0.01, P〈0.05）, while that of cerebral Nogo-A was significantly decreased at the two time-points in the EA group （P〈0.01）. Conclusion EA intervention can effectively improve neurological function in cerebral infarction rats, which is closely related to its effects in upregulating cerebral VEGF, GAP-43, SYN and MBP expression, and down-regulating Nogo-A protein, suggesting a protective effect on neurovascular unit.