“通督调神固本”电针法对高血压-高血脂复合血管性痴呆模型大鼠学习记忆干预的初步研究

目的:观察电针对高血压-高血脂复合血管性痴呆(HH-VD)模型大鼠学习记忆能力、脑细小血管、海马及基础病理变化的影响。方法:SD大鼠随机分为假手术组、模型组、电针Ⅰ组、电针Ⅱ组和西药组,每组8只。"双肾一夹"法复制高血压模型,喂高脂饲料复制高血压复合高血脂模型,再采用二血管阻断法复制HH-VD模型。电针Ⅰ组取"百会"大椎"脾俞"肾俞"穴,电针Ⅱ组取非经穴,西药组用尼莫地平按20mL/kg灌胃,均每日1次,共治疗15d。对各组大鼠进行行为学检测,并电镜观察海马CA1区突触情况,光镜观察脑组织的病理改变。结果:与假手术组比较,模型大鼠Y迷宫测试其错误次数(EN)、总反应时间(TRT)和达标反应次数(SN)均显著升高(P<0.01);电镜下观察,模型大鼠海马CA1区突触明显减少,突触后致密物质(PSD)浅淡;光镜下模型大鼠脑组织细、小动脉硬化明显。治疗后,电针Ⅰ组、电针Ⅱ组、西药组大鼠的EN、TRT、SN显著降低,与模型组比较差异有统计学意义(P<0.01),电针Ⅰ组、西药组的EN、TRT、SN又低于电针Ⅱ组(P<0.05);电镜观察,电针Ⅰ组海马CA1区突触数目最多,PSD密度大;光镜下电针Ⅰ组脑组织血管形态与假手术组十分接近。结论:"通督调神固本"电针法能改善HH-VD模型大鼠的脑血管异常,增加海马突触数目,增强其活性,有效提高其学习记忆能力。

Effect of Electroacupuncture on Learning-memory Ability of Vascular Dementia Rats with Concomitant Hypertension and Hyperlipemia

Objective To observe the effect of electroacupuncture(EA)of acupoint recipe for"dredging Governor-Meridian,regulating vitality and strengthening the kidney"on learning-memory ability and pathological changes of cerebral minute blood vessels and hippocampal structure in hypertension-hyperlipmia-vascular dementia(HH-VD)rats.Methods Forty SD rats were randomly divided into sham-operation(sham)group(n=8),EA-Ⅰ groupn=8,EA of"Baihui"(GV 20),"Dazhui"(GV 14),"Pishu"(BL 20)and"Shenshu"(BL 23),80 Hz,1 mA,20 min/day,15 days],EA-Ⅱgroup(n=8,EA of nonpoints.5 mm lateral to the abovementioned acupoints),medication group(n=8,intragastric perfusion of Nimotong,0.6 mg/mL,20 mL/kg.15 days),model group(n=8).HH-VD model was established by feeding the rat with high fat forage and by occlusion of the left renal artery and carotid artery.The animals' learning-memory ability was detected by Y-maze test,the synaptic structure of the hippocampal CA 1 region,and the pathological change of the cerebral cortex were observed by electronic microscope and light microscope,respectively.Results After modeling,the blood pressure,serum total cholesterol and triglyceride(TG)levels,and the error number(EN),total reaction time(TRT)and standard number(SN,number of paw-electric-stroke for reaching correct reactions)of Y maze test increased significantly in comparison with sham group(P＜0.05)After EA,the EN,TRT and SN of EA-Ⅰ,EA-Ⅱand medication groups decreased significantly in comparison with model group(P＜0.0 1),suggesting astriking improvement of the learning-memory ability after the treatment,and the EN,TRT and SN of EA-Ⅰ group and medication group were significantly lower than those of EA-Ⅱgroup(P＜0.05)Under electronic microscope,the number of synapses in hippocampal CA 1 area of HH-VD model rats reduced obviously,its postsynaptic density(PSD)was lighter.and the synaptic vesicles were fewer.Whereas in comparison with EA-Ⅱand medication groups,the synaptic number and density in EA-Ⅰ group were more and bigger,and the width,length and color of PSD increased clearly.The synaptic number of EA-Ⅱ group was relatively smaller compared with the other two treatment groups,Under light microscope,the vascular walls of the cerebral minute and small arteries of model group were obviously thickened and their lumina narrowed While in EA-Ⅰ group,these pathological changes were mild.In medication group the thickening of vascular walls of partial cerebral minute and small arteries were also seen.Conclusion EA of acupoint recipe for"dredging Governor-Meridian,regulating vitality and strengthening the kidney"can improve pathological changes of the synaptic structure of hippocampal CA 1 region and the vascular walls of cerebral minute and small arteries,which may contribute to its function in improving the learning-memory ability in HH-VD rats.