电针对高血压脑梗死大鼠皮层、延髓及颈髓Rac-1蛋白表达的影响

Effect of electric acupuncture on expression of central nerve growth proliferation differentiation mediated factor Rac-1 in the cerebral cortex, medulla oblongata, cervical spinal cord of strokeprone-renovascular-hypertensive rats

目的观察电针对易卒中型肾性高血压大鼠（RHRSP）大脑中动脉闭塞（MCAO）后缺血再灌注不同时间点大脑皮层、延髓、颈髓RacGTP酶激活蛋白-1（Rac—1）表达的影响，探讨电针治疗急性脑梗死（ACI）远隔损害的可能机制。方法480只雄性SPF级SD大鼠行双肾双夹术复制RHRSP模型，再用线栓法制作MCAO模型，按照随机数字表法分为高血压组、假手术组、模型组、电针组、假针刺组，每组60只。高血压组大鼠为单纯RHRSP模型：假手术组大鼠在RHRSP模型基础上行MCAO手术创伤（不栓塞）；模型组大鼠行MCAO术后予以缺血再灌注处理：电针组大鼠在模型组大鼠基础上选取督脉“百会”和“大椎”穴进行电针治疗，每天1次，共28d。假针刺组将针灸针贴于大鼠“百会”和“大椎”穴处皮肤。MCAO造模后第1、7、14、28天分别处死各组大鼠．分离出右侧大脑、延髓和左侧颈髓，Western blotting检测Rac．1蛋白表达。结果（11皮层区：MCAO术后第7、14、28天，脑梗死组、电针组、假针剌组大鼠Rac-1的表达较高血压组、假手术组明显降低；电针组大鼠Rac．1表达较脑梗死组明显升高，差异均具有统计学意义（P〈0．05）。（2）延髓区：MCAO术后第14、28天，脑梗死组、电针组、假针刺组大鼠Rac-1表达较高血压组、假手术组明显降低：电针组大鼠Rac-1表达较脑梗死组明显升高，差异均具有统计学意义fP〈0．05）。（3）颈髓区：MCAO术后第28天，脑梗死组、电针组、假针刺组大鼠Rac-1表达较高血压组、假手术组明显降低；电针组Rac-1表达较脑梗死组、假针刺组明显升高，差异均具有统计学意义（P〈0．05）。结论RHRSP模型脑梗死后皮层、延髓与颈髓Rac-1表达降低是ACI远隔损害的重要原因，电针对高血压大鼠脑梗死中枢神经损伤的保护作用可能与其上调Rac-1表达有关。

Objective To observe the effect of electric acupuncture on expression of central nerve growth proliferation differentiation mediated factor Rac-1 in cerebral cortex, medulla oblongata, cervical spinal cord of stroke-prone-renovascular-hypertensive rats （RHRSP） at different times of middle cerebral artery occlusion （MCAO） and cerebral ischemia reperfusion, and investigate the mechanisms of electric acupuncture in remote damage of acute cerebral infarction （ACI）. Methods Forty hundred and eighty male SPF SD rats were duplicated to RHRSP models and created MCAO models by stringing middle cerebral artery; and then, these rat models were divided into hypertension group, sham-operated group, cerebral infarction group, electric acupuncture group and sham electric acupuncture group by random number table method （n=60）. Rats in the hypertension group were only performed RHRSP; rats in the sham-operated group only received surgical trauma; rats in the cerebral infarction group received reperfusion after MCAO; ＂Baihui＂ and ＂Dazhui＂ acupoints were electroacupuncted in rats of electric acupuncture group once daily for a consecutive 28 d; sham electric acupuncture group received electric acupuncture with the needles stick to the skin of ＂Baihui＂ and ＂Dazhui＂ acupoints. One, 7, 14, 28 d after treatment, 6 rats in each groups were put to death, respectively, and isolated the right side of the cortex and medulla oblongata and the left side of the spinal cord. The Rac-1 expression was detected by Western blotting. Results Cortex area： 7, 14, 28 d after MCAO, lower Rac-1 expression in the cerebral infarction group, electric acupuncture group and sham electric acupuncture group was noted as compared with that in the hypertension group and sham-operated group （/＇〈0.05）; electric acupuncture group had significantly higher Rac-1 expression than the cerebral infarction group and sham electric acupuncture group （P〈0.05）. Medulla oblongata area： 14, 28 d aider MCAO, lower Rac-1 expression in the cerebral infarction group, electric acupuncture group and sham electric acupuncture group was noted as compared with that in the hypertension group and sham-operated group （P〈0.05）; electric acupuncture group had significantly higher Rat-1 expression than the cerebral infarction group and sham electric acupuncture group （P〈0.05）. Spinal cord area： 28 d after MCAO, lower Rac-1 expression in the cerebral infarction group, electric acupuncture group and sham electric acupuncture group was noted as compared with that in the hypertension group and sham-operated group （P〈0.05）; electric acupuncture group had significantly higher Rac-1 expression than the cerebral infarction group and sham electric acupuncture group （P〈0.05）. Conclusions The decreased Rac-1 expression in the cerebral cortex, medulla oblongata and spinal cord of cerebral infracted RHRSP may be an important factor which involves ACI remote damage. Electric acupuncture＇s protection to central nervous of cerebral ischemic RHRSP may closely relate to the mechanism of its up-regulation effect of Rac-1 expression.