不同频率头部电针对脑梗死大鼠NRG-1表达影响研究

Effect of Head Electroacupuncture with Different Frequency on the Expression of NRG-1 in Rats with Cerebral Infarction

目的观察不同频率头部电针对脑梗死大鼠运动功能及神经调节蛋白1(NRG-1)表达的影响,探讨头部电针治疗脑梗死的相关机制。方法将60只大鼠随机分为空白组、假手术组、模型组,2、50和100 Hz电针组,每组10只。采用线栓法进行大脑中动脉闭塞(MCAO)模型的制备。电针组大鼠取百会、前神聪向病侧透刺,针刺深度约0.5寸,频率为2、50和100 Hz,连续波,每次20 min,每日1次,治疗14 d。空白组、假手术组和模型组大鼠仅做相同的绑缚处理。在治疗第1、3、5、7、14天,进行前肢抓握牵引试验评分,末次治疗后取材。用酶联免疫吸附法(ELISA)检测大鼠右侧脑组织NRG-1的表达含量,并分析大鼠行为学评分与NRG-1表达的相关性。结果与假手术组比,模型组运动功能下降(P<0.05),NRG-1的表达含量增加(P<0.01)。与模型组比,治疗第7天开始各电针组运动功能优于模型组(P<0.01);2 Hz和50 Hz电针组NRG-1表达含量高于模型组(P<0.01和P<0.05)。不同频率电针组组间比较,在治疗第5、14天,2 Hz电针组大鼠的运动功能优于50 Hz电针组和100 Hz电针组(P<0.05),50 Hz和100 Hz电针组未见组间疗效差异(P>0.05);2 Hz电针组NRG-1的表达高于50 Hz和100 Hz电针组(P<0.05和P<0.01)。2 Hz电针组大鼠的运动功能评分与NRG-1的表达量呈正相关(P<0.01)。结论不同频率头部电针能够改善脑梗死大鼠前肢运动功能,其中2 Hz疗效最优,其机制可能与其上调缺血区NRG-1的表达有关。

Objective To observe the effect of head electroacupuncture with different frequency on motor function and expression of NRG-1 in rats with cerebral infarction,and to explore the mechanism of head electroacupuncture in the treatment of cerebral infarction.Methods 60 rats were randomly divided into blank group,sham operation group,model group,2 Hz,50 Hz and 100 Hz electroacupuncture group,10 rats in each group.The model of middle cerebral artery occlusion(MCAO)was established by thread occlusion.In the electroacupuncture group,rats were punctured to the diseased side by Baihui(DU20)and Qianshencong(EX-HNI),the depth of acupuncture was about 0.5 inch,the frequency was 2 Hz,50 Hz and 100 Hz,continuous wave,each time for 20 minutes,once a day,14 days.The rats in the blank group,sham operation group and model group only received the same binding treatment.On the first,third,fifth,seventh and fourteenth day of the treatment,the traction test scores of the forelimb were made,and the materials were taken after the last treatment.Immunohistochemistry was used to observe the expression of NRG-1 positive cells,AOD was calculated,enzyme-linked immunosorbent assay(ELISA)was used to detect the expression of NRG-1 in the right brain of rats,and the correlation between behavioral score and NRG-1 expression was analyzed.Results Compared with the sham operation group,the motor function of the model group decreased(P<0.05),and the AOD value and expression content of NRG-1 increased(P<0.01).Compared with the model group,the motor function of each electroacupuncture group was better than that of the model group(P<0.01)from the 7th day of treatment;the NRG-1 expression and AOD value of the 2 Hz and 50 Hz electroacupuncture group were higher than that of the model group(P<0.01 and P<0.05).Compared with different frequency electroacupuncture groups,on the 5th and 14th day of treatment,the motor function of rats in 2 Hz electroacupuncture group was better than that in 50 Hz electroacupuncture group and 100 Hz electroacupuncture group(P<0.05).There was no difference in the therapeutic effect between 50 Hz and 100 Hz electroacupuncture group(P>0.05);the expression of NRG-1 in 2 Hz electroacupuncture group was higher than that in 50 Hz and 100 Hz electroacupuncture group(P<0.05 and P<0.01).There was a positive correlation between the score of motor function and the expression of NRG-1 in 2 Hz electroacupuncture group(P<0.01).Conclusion Electroacupuncture at different frequencies can improve the motor function of the forelimb in rats with cerebral infarction,of which 2 Hz is the most effective.The mechanism may be related to the up regulation of NRG-1 expression in the ischemic area.