电针对局部脑缺血大鼠脑内P物质表达的影响研究

Effect of Electroacupuncture on Expression of Substance P in Brain of Rats with Partial Cerebral Ischemia

目的探讨电针是否通过调节脑内P物质水平参与局部缺血性脑损害的恢复,从而改善脑循环,发挥脑保护作用。方法雄性清洁级SD大鼠32只,按数字随机表法分为空白组、假手术组、模型组及电针组,每组8只大鼠,采用Longa线栓方法建立左侧大脑中动脉梗塞模型,在成功制作出局部脑缺血模型并根据chen等神经功能缺损评分标准判定造模情况。对造模成功并入组的大鼠电针双侧"足三里"穴,刺激参数为频率20 Hz疏密波,强度以2 mA起,每10 min增加1 mA,持续电针30 min,14 d后检测各组大鼠大脑皮质运感区、海马、小脑等脑组织的P物质表达。结果大鼠小脑区域P物质表达电针组较模型组有明显增加(P<0.05),而皮质运感区及海马电针组与模型组无明显差异。结论 P物质作为参与痛觉反应的神经肽,其在小脑的下行调制纤维中的大量表达有关,而这种表达有可能参与了对局部血流量的改善。

Objective To explore whether electroacupuncture play a role in the recovery of ischemic brain damage by regulating the substance P in brain, so as to improve the cerebral circulation and protect the cerebrums. Methods 32 male SD rats were randomly divided into blank group （n=8）, sham operation group （n = 8）, model group （n = 8） and electroacupuncture group （n = 8） according to the random number table method. The middle cerebral artery occlusion rat model was established by the Longa occlusion method, the model was checked by using chen neurologic impairment score, then bilateral Zusanli （ST36） of rats with successful modeling was stimulated by electroacupuncture for 30 minutes （frequency was 20 Hz, beginning in- tensity was began from 2 mA and increased by 1 mA every 10 minutes）. After 14 days, the levels of substance P in sensory and motor areas of the cerebral cortex, hippocampus and cerebellums of rats in each group were determined. Results The level of substance P in cerebellums of rats in electroaeupuncture group was higher than that of model group （P〈0.05）, but there was no significant difference in sensory and motor areas of the cerebral cortex and hippoeampus between the two groups. Conclusion Neuropeptide substance P which takes part in pain modulation strongly expresses in downstream modulation fiber of cerebellum, and this expression may play a role in the improvement of regional blood flow.