电针对脑缺血再灌注大鼠学习记忆能力及血管内皮生长因子表达的影响

Effect of Electroacupuncture on Learning and Memory Ability and Expression of VEGF in Rats after Middle Cerebral Artery Occlusion/Reperfusion

目的研究电针对脑缺血/再灌注大鼠梗死侧海马区血管内皮生长因子(VEGF)、内源性神经干细胞(NSCs)及学习记忆功能的影响。方法将40只雄性SD大鼠随机分为正常组、假手术组、模型组及电针组,每组10只动物,模型组及电针组大鼠采用Zea Longa线栓法制备局灶性脑缺血/再灌注(MCAO/R)模型,电针组于制备模型后24h给予电针治疗,连续治疗14d后,采用RT-PCR法检测梗死侧海马区VEGF mRNA的表达,免疫组化法检测梗死侧海马区内源性神经干细胞的增殖,水迷宫检测其学习记忆能力。结果与模型组比较,电针治疗组大鼠脑梗死侧海马区VEGFmRNA表达明显增强,内源性神经干细胞增殖显著增加,而逃避潜伏期明显缩短,差异均有统计学意义(均P<0.01)。结论电针可能通过增加脑梗死侧海马区VEGF的表达而促进血管新生,进而诱导内源性神经干细胞的增殖,从而改善其学习记忆能力。

Objective To study the effect of electroacupuncture on the expression of vascular endothelial growth factor （VEGF） ,and endogenous neural stem cells （NSCs） in the hippocampus of infarctied side of rats after middle cerebral artery occluSion/reperfusion infarction,and the ability of learning and memory of rats. Methods Forty male SD rats were randomly divided into normal, sham operation,ischemia and electroacupuncture groups with 10 rats in each. The focal cerebral ischemia and reperfusion models were established by thread-occlusion of the middle cerebral artery in the latter two groups. Electroacupunc- ture was performed 24 h after reperfusion and lasted for 14 consecutive days. The expression of VEGF mRNA in the cerebral is- chemia tissue was detected by using RT-PCR,and the proliferation of endogenous NSCs in the hippocampus of infarctied side of rats by immunohistochemistry. The ability of learning and memory was assessed by Morris water maze test after 14-day treatment. Results The mRNA expression level of VEGF in the hippocampus of infarctied side was increased obviously in electroacupuncture group as compared with the model group （P〈0.01）. The proliferation of endogenous NSCs was substantially enhancedin the electroacupuncture group as compared with the model group （P〈0. 01）. The escape latency in the electroacupuncture group was decreased as compared with the model group （P〈0.01）. Conclusion Electroacupuncture therapy may improve the ability of learning and memory of rats with cerebral ischemia-reperfusion by increasing the expression of VEGF mRNA, promoting angiogenesis and inducing the proliferation of endogenous NSCs in the cerebral infarction area.