电针“内关”“天枢”穴对肠易激综合征大鼠结肠动力及结肠D2受体的影响

摘要

目的:观察并比较电针“天枢”“内关”穴对肠易激综合征(IBS)大鼠结肠动力及结肠多巴胺D2受体表达的影响,探讨不同经脉和不同穴性穴位的效应特异性.方法:Wistar新生大鼠随机分为空白对照组、模型对照组、天枢组和内关组,每组10只.采用母子分离与醋酸灌肠再结合结直肠扩张的方法制备IBS大鼠模型.天枢组和内关组分别给予双侧“天枢”和“内关”电针干预,隔日治疗1次,共5次.记录大鼠Bristol粪便评分、腹部回撤反射的第1次收缩波潜伏期和90 s内收缩波个数及免疫组化法检测结肠多巴胺D2受体的表达.结果:与空白对照组相比,模型对照组大鼠的Bristol评分显著增高(P＜0.01),第1次收缩波潜伏期明显缩短(P＜0.01),90 s内收缩波个数明显增多(P＜0.01),结肠内D2受体免疫反应物阳性表达水平明显下降(P＜0.01).与模型对照组相比,天枢组和内关组大鼠治疗后的Bristol评分均显著下降(P＜0.01),第1次收缩波潜伏期均明显延长(P＜0.01),90 s内收缩波个数明显减少(P＜0.01),结肠内D2受体免疫反应物阳性表达水平明显增强(P＜0.01,P＜0.05).与天枢组相比,内关组结肠内D2受体免疫反应物阳性表达水平下降(P＜0.01).结论:电针“天枢”“内关”穴均可明显改善IBS大鼠的结肠动力异常症状,但电针“天枢”穴的效应更佳,说明不同经脉和穴性的穴位存在效应特异性.%Objective To observe and compare the effects of electroacupuncture (EA) at "Tianshu" (ST 25) and "Neiguan" (PC 6) for colonic motility and the expression of colon dopamine D 2 in irritable bowel syndrome (IBS) rats,and to explore the specificity of different meridians and different acupoints.Methods Forty Wistar newborn rats were randomly divided into blank,model,Tianshu and Neiguan groups.Separation of mother and child and acetic acid coloclyster combined with colorectal distension were used to establish IBS model in the model,Tianshu and Neiguan groups.At the age of 9 weeks,EA at bilateral ST 25 and PC 6 were applied in the corresponding groups 5 times,once every other day.After the intervention,the Bristol fecal score,the latent period of abdominal retraction reflex and the number of contraction waves were recorded.The expression of dopamine D 2 receptor was detected by immunohistochemistry.Results Compared with the blank group,the Bristol fecal score of the model group was higher (P＜0.01),the 1st contraction wave latent period was shorter (P＜0.01),the number of contraction waves in 90 s increased (P＜0.01),the immunoreactive expression of D 2 receptor in colon decreased (P＜0.01).Compared with the model group,the Bristol fecal scores of the Tianshu and Neiguan groups decreased (P＜0.01),the 1st contraction wave latent periods were longer (P＜0.01),the numbers of contraction waves in 90 s decreased (P＜0.01),the positive expressions of D 2 receptor in colon increased (P＜0.01,P＜0.05).Compared with the Tianshu group,the immunoreactive expression of D 2 receptor in the Neiguan group decreased (P＜0.01).Conclusion EA at ST 25 and PC 6 can improve the symptoms of colonic motility in IBS rats.The effect of EA at ST 25 is better,which indicates that different meridians and different acupoints play specific effects.