针刺对脑梗死大鼠脑血管平滑肌蛋白激酶C的影响

Effect of Electroacupuncture Intervention on Expression of Vascular PKC in the Ischemic Cerebral Tissue in Rats with Cerebral Infarction

目的:观察针刺对脑梗死大鼠脑血管平滑肌蛋白激酶C(PKC)变化的动态调节规律。方法:雄性Wistar大鼠,随机分为模型组(24只)、针刺组(24只)、假手术组(24只)和空白组(6只),前3组又分为大脑中动脉阻滞(MCAO)后0.5、1、3、6h4个时相组,每组6只。以线栓法复制脑梗死大鼠模型。针刺组在MCAO后即刻针刺"水沟"穴,电针刺激20min。各组动物均按时相处死,在外科显微镜下分别分离和剪取梗死侧的大脑前动脉、中动脉和后动脉各8mm。应用免疫组化、免疫印迹法分别检测脑血管平滑肌PKC的变化。结果:免疫组化与免疫印迹结果均显示,与空白组相比,模型组MCAO后各时相PKC表达均上调(P<0.05,P<0.01),针刺组PKC表达均较模型组下调(P<0.01,P<0.05)。结论:针刺干预可显著抑制MCAO模型大鼠脑表面血管PKC表达上调趋势,使其维持在正常值左右,这对于缓解脑缺血后血管平滑肌痉挛具有重要作用。

Objective To observe the effect of electroacupunctur （EA） of Shuigou（GV 26）on the expression of vascular protein kinase C （PKO） in the focal ischemia cerebral tissue in rats so as to study its dynamic regulation mechanism. Methods A total of 78 Wistar rats were randomly divided into model group （ n = 24）, EA group（ n = 24）, sham operation （sham） group （n = 24） and control group （n = 6）. The first 3 groups were further divided into 0.5 h, 1 h, 3 h and 6 h subgroups, with 6 cases in each. Cerebral ischemia （OI） model was established by occlusion of the middle cerebral artery. EA （ 15 Hz, 1.0 mA） was applied to ＂Shuigou＂ （GV 26） for 20 rain. The anterior, middle and posterior cerebral arteries on the infarct side of the brain were collected for assaying the expression of PKC protein by using Western blot, and the formalin-fixed artery samples were embedded with paraffin, followed by sectioning and staining with immunohistochemistry. Results Compared with the control group, the expression levels of cerebral vascular smooth PKC protein shown by both immunohistochemistry and Western blot were upregulated sig- nificantly at the time-points of 0.5 h, 1 h, 3 h and 6 h after OI in the model group （P〈0.05, P〈0.01）. In comparison with the model group, the expression levels of PKC protein in the cerebral vascular smooth muscle shown by the aforementioned two methods were down-regulated considerably in the EA group （P〈0.01, P〈0.05）. No statistic differences were found between the control and sham groups in the expression of vascular PKO protein at different time-points （P〉0.05）. Conclusion EA intervention can significantly inhibit PKO expression in the cerebral vascular smooth muscle in CI rats, which may be responsible for its efficacy in im- proving ischemic stroke.