电针对局灶性脑缺血大鼠神经功能、脑血流及脑组织细胞色素P450表氧化酶基因表达的影响

目的:观察电针对局灶性脑缺血大鼠脑组织细胞色素P 450表氧化酶(cytochrome P 450epoxygenase,CYP 2C11)mRNA表达的影响,探讨针刺治疗缺血性脑血管疾病的可能机制。方法:Wistar大鼠随机分为正常组、模型组、电针组和电针+17-ODYA组,每组8只。采用线栓法复制局灶性脑缺血大鼠模型。电针+17-ODYA组造模同时侧脑室注射17-十八炔酸。电针各组电针双侧"内关"穴和"曲池"穴,刺激20min,每天1次,共治疗7d。观察大鼠治疗前后神经功能恢复情况,观察脑组织形态学变化,采用激光多普勒检测大鼠软脑膜微循环血流量,实时荧光定量检测脑组织CYP 2C11mRNA表达的变化。结果:模型组大鼠脑组织呈现不同程度的萎缩、液化及坏死,大量胶质细胞增生及血管增生,可见海马锥体细胞的损伤,严重者锥体细胞片状消失;电针组大鼠脑组织萎缩、液化及坏死程度与模型组比较显著减轻,神经细胞数目较模型组大鼠明显增多,坏死细胞减少,细胞及血管周围间隙明显缩小,修复范围较大;电针+17-ODYA组大鼠脑组织缺血坏死程度大于电针组。模型组神经功能评分明显高于正常组(P0.05),电针组神经功能评分低于模型组及电针+17-ODYA组(均P0.05)。模型组走横木实验(BWT)评分较正常组明显降低(P0.05),电针组BWT评分较模型组及电针+17-ODYA组明显升高(均P0.05)。模型组软脑膜微循环血流量低于正常组(P0.05),电针组软脑膜微循环血流量较模型组及电针+17-ODYA组显著升高(均P0.05)。模型组CYP 2C11mRNA表达较正常组明显增强(P0.05),电针组CYP 2C11mRNA表达较模型组及电针+17-ODYA组进一步升高(均P0.05)。结论:针刺可通过上调CYP 2C11mRNA表达,进而促进脑微循环血流量的改善,血流量的增加有助于增加脑组织氧供应,改善因缺血而减退的神经元代谢,减少神经元损伤,促进神经修复,改善神经功能。

Effect of Electroacupuncture Intervention on Neurological Function,Cerebral Blood Flow and Cerebral Cytochrome P 450 2C11mRNA Expression in Rats with Focal Cerebral Ischemia

Objective To observe the effect of electroacupuncture(EA)intervention on changes of neurological function and expression of cerebral cytochrome P 450 2C11(CYP 2C11)mRNA in focal cerebral ischemia(FCI)rats,so as to explore its mechanism underlying improvement of ischemic cerebral vascular disease.Methods Wistar rats were randomly divided into normal,model,EA and EA+17-ODYA(17-Octadecynoic acid,an inhibitor for the metabolism of arachidonic acid by cytochrome P 450)groups.Focal cerebral ischemia rats were induced by middle cerebral artery occlusion(MCAO)with thread embolus.EA was applied to bilateral"Neiguan"(PC 6)and"Quchi"(LI 11)after MCAO.Zea Longa's score and beam walking test(BWT)score of rats were used to evaluate the neurological impairment.Local cerebral blood flow(LCBF)of the pial tissue was monitored using Laser-Doppler Flowmetry.The expression of cerebral CYP 2C11 mRNA was examined by Real-time Quantitative PCR(qPCR).Results In comparison with the normal group,BWT score and LCBF of the model group were significantly decreased(P<0.05),and Zea Longa's score and cerebral CYP 2C11 mRNA expression level of the model group were significantly increased(P<0.05).While in comparison with the model group,BWT score,LCBF and cerebral CYP 2C11 mRNA levels were considerably up-regulated and Zea Longa's score was down-regulated in the EA group(P<0.05)rather than in the EA+17-ODYA group(P<0.05).H.E.stain showed that the nerve impairment of the ischemic cerebral tissue including the neuronal degeneration,necrosis,apoptosis,etc.was relatively milder in the EA group.Conclusion EA intervention can improve cerebral blood flow and up-regulate cerebral CYP 2C11 mRNA expression in FCI rats,which may contribute to its action in improving neurological impairment.