电针对缺血再灌注大鼠脑内小胶质细胞活化的影响

Effect of electroacupuncture on activation of brain microglial cells in rats with ischemia-reperfusion injury

目的:探讨电针对缺血再灌注损伤模型大鼠脑内小胶质细胞活化的抑制作用。方法:将54只SD大鼠随机分为假手术组(6只)、模型组(24只)、电针组(24只),再将模型组、电针组分成再灌注3、12、24、48h 4个亚组,每亚组6只。模型组、电针组予制备缺血再灌注模型,其中模型组造模后不予电针治疗,电针组造模后即行电针治疗,取穴百会和大椎。各组大鼠到达预定时间点,将脑组织固定在4%多聚甲醛固定液中保存,行免疫组化染色,检测OX-42阳性小胶质细胞的活化情况。结果:各组缺血再灌注模型大鼠缺血侧顶叶皮层OX-42阳性细胞数较假手术组增多,差异具有统计学意义(P<0.01);模型组OX-42阳性细胞在R3h明显增多,R24h达高峰,然后呈下降趋势;R24h与R3h相比,差异具有统计学意义(P<0.01);电针组OX-42阳性细胞数较模型组均有所减少,除R3h外,其余各组差异均有统计学意义(P<0.05)。结论:电针百会穴、大椎穴能抑制缺血再灌注损伤模型大鼠脑内小胶质细胞的活化,从而起到神经保护的作用。

Objective： To investigate the inhibitory effect of electroacupuncture on the activation of brain microglial cells in the rat model of ischemia-reperfusion injury. Methods： Fifty-four Sprague-Dawley rats were randomly divided into sham-operation group（ n = 6）,model group（ n = 24）,and electroacupuncture group（ n = 24）. Each rat in the model group and electroacupuncture group underwent ischemia-reperfusion for 3,12,24,or 48 h,with 6 rats in each subgroup. After the rat model of ischemia-reperfusion injury was established,the rats in the electroacupuncture group received electroacupuncture at Baihui and Dazhui acupoints. After treatment,brain tissues were fixed in 4% polyoxymethylene solution and subjected to immunohistochemical staining; the activation of OX-42-positive microglial cells was assessed. Results： Compared with the sham-operation group,the rats with ischemia-reperfusion injury had a significantly increased number of OX-42-positive microglial cells in the parietal cortex on the ischemic side（ P 0. 01）. In the model group,the number of OX-42-positive microglial cells significantly increased at 3 h,reached the peak level at 24 h,and then decreased; there was a significant difference between the values at 24 h and 3 h（ P 0. 01）. Compared with the model group,the electroacupuncture group had a reduced number of OX-42-positive microglial cells,with significant differences at all time points except at 3 h（ P 0. 05）. Conclusion： Electroacupuncture at Baihui and Dazhui acupoints can inhibit the activation of brain microglial cells in the rat model of ischemia-reperfusion injury,thus exerting the neuroprotective effect.