电针对局灶性脑梗死大鼠皮质Slit2/Robo1表达的影响

Effect of Electroacupuncture of "Neiguan"(PC 6) and "Zusanli"(ST 36) on Expression of Cerebral Cortical Slit 2/Robo 1 in the Focal Cerebral Infarction Rats

目的:观察局灶性脑梗死大鼠皮质Slit 2/Robo 1的表达及电针干预对其表达的影响,探讨Slit2/Robo 1在电针对脑梗死后神经可塑性影响中的作用。方法:雄性SD大鼠随机分为正常组、模型组和电针组,后两组再根据缺血时间随机分为1、3、7、14d4个亚组,每组各10只。用线栓法制作大脑中动脉闭塞模型。电针组取"内关""足三里",留针30min,每日治疗1次。在第1、3、7、14天分别利用免疫组织化学法和免疫印迹法检测缺血侧大脑皮质Slit 2和Robo 1的表达。结果:免疫组化和免疫印迹法检测结果显示,与正常组相比,模型组Slit 2表达水平在术后1d即开始上升(P<0.05,P<0.01),3d时升高达高峰(P<0.01),14d时回落到基础水平(P>0.05);电针组与模型组同时间点相比均呈现高表达(P<0.05,P<0.01),电针组Slit 2高峰出现在术后7d。与正常组相比,模型组Robo 1表达水平在术后1d即开始上升(P<0.05,P<0.01),3d时升高达高峰(P<0.01),免疫印迹结果显示14d时仍高于基础水平(P<0.01);电针组与模型组相比,1、7、14d时呈现更高表达(P<0.01,P<0.05)。结论:局灶性脑梗死后大鼠皮质Slit 2/Robo 1表达明显上调,给予电针干预后可提高其表达峰值并延长高表达时间,这可能是电针促进脑梗死后神经功能恢复的机制之一。

Objective To observe the effect of electroacupuncture （EA） intervention on expression of Slit 2 and its transmembrane receptor Robo 1 in the cortex tissue of cerebral infarction rats so as to study its mechanism underlying improvement of cerebral ischemia. Methods Ninety male Sprague Dawley rats were randomly divided into control group （n = 10）, model group （n = 40） and EA group （n = 40）, and the latter two groups were further randomized into four subgroups： 1 d, 3 d, 7 d, and 14 d （n = 10 in each subgroup） according to the cerebral ischemia duration. Cerebral infarction model was established by occlu-sion of the middle cerebral artery （MCAO）. EA （80-100 Hz, 1-3 mA） was applied to bilateral ＂Neiguan＂ （PC 6） and ＂Zusanli＂ （ST 36） for 30 min, once daily for 1 d, 3 d, 7 d, and 14 d, respectively. The animals＇ neurological defect was assessed using Zea-Longa scoring. The expression of Slit 2 and Robol proteins in the cerebral cortex on the ischemic side was assayed using im-munohistochemistry and Western blotting, respectively. Results In comparison with the control group, the neurological score was significantly higher in the model group （ P〈0.05）, and reduced considerably on day 7 and 14 after MCAO in the EA group compared with the model group （P〈0.05）. Immunohistochemical results showed that in comparison with the control group, the immunoactivity levels of cerebral Slit 2 and Robo 1 were remarkably upregulated on day 1, 3 and 7 after MCAO in the model group （ P〈0.05, P〈0.01）, and backed to the control levels on day 14 （P〉0.05）. While compared with the model group, the immu-noactivity levels of cerebral Slit 2 and Robo 1 were further obviously upregulated on day 1, 3, 7 and 14 after cerebral ischemia in the EA group （ P〈0.05, P〈0.01 ）. The results of Western blotting about the expression levels of cerebral Slit 2 and Robo 1 pro-teins were nearly the same to those of immunohistochemical outcomes in the 4 subgroups apart from that the expression levels of both Slit 2 and Robo 1 proteins were still obviously higher on day 14 after EA intervention can significantly improve cerebral ischemia rats＇ neurologica cerebral Slit 2 and Robo 1 proteins, which may be one of the mechanisms of MCAO in the model group （P〈0. 01）. Conclusion I function and obviously upregulate the expression of EA therapy for relieving cerebral infarction in clinic.