Yao Jun-Peng, Zhao Yan, Chen Ying, Chen Li-Ping, Feng Xiu-Mei, Li Ying, Zhou Si-Yuan
College of Acupuncture-moxibustion and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China.
Department of Pain, Shenzhen People's Hospital, Shenzhen 518020, Guangdong Province.
Zhen Ci Yan Jiu. 2020 May 25;45(5):357-62. doi: 10.13702/j.1000-0607.190285.
To observe the effect of electroacupuncture (EA) on intestinal epithelial mucosal barrier function in diarrhea-predominant irritable bowel syndrome(IBS-D) rats, so as to explore its mechanisms underlying improvement of IBS-D.
Forty SD rats (half male and half female) were randomly divided into control, model, EA and medication (Pinaverium Bromide, PB) groups, with 10 rats in each group. The IBS-D model was established by chronic unpredictable mild stress combined with gavage of Senna-leaf solution. EA (2 Hz/15 Hz，0.1-1 mA) was applied to unilateral "Zusanli"(ST36),"Tianshu" (ST25), "Sanyinjiao"(SP6) and "Taichong"(LR3) alternatively for 15 min, once daily for 14 days. Rats of the medication group was treated by gavage of PB (10 mL·kg·d) for 14 days. The visceral sensitivity (pain) was assessed by using the pressure threshold which the inserted rectal balloon catheter air-inflation (connected to a blood pressure gauge) induced stronger abdominal muscular contraction to force the rat's abdomen to lift the experimental stand surface. The diarrhea index was used to evaluate loose stool grade. The expression of Claudin-1 and Occludin (intestinal epithelial tight junction proteins) of colon tissue was detected by immunohistochemistry. The activity of plasma diamine oxidase (DAO) was assayed by using spectrophotometry.
Compared with the control group, the diarrhea index and plasma DAO activity in the model group were significantly increased (<0.01), while the visceral pain threshold, expression of Claudin-1 and Occludin in the model group were significantly decreased (<0.01). After the treatment, the diarrhea index and plasma DAO activity were significantly lower in both EA and medication groups than that in the model group (<0.01), and the visceral pain threshold and expression levels of Claudin-1 and Occludin were obviously increased (<0.05, <0.01). No significant differences were found between the EA and medication groups in all the above-mentioned indexes (>0.05).
Electroacupuncture can significantly improve abdominal pain and diarrhea in IBS-D model rats, which may be closely associated with its effects in up-regulating the expression of intestinal epithelial tight junction proteins Claudin-1 and Occludin to restore the function of intestinal epithelial mucosal barrier.
观察电针（EA）对腹泻型肠易激综合征（IBS-D）大鼠肠上皮黏膜屏障功能的影响，以探讨其改善IBS-D的作用机制。
将40只SD大鼠（雌雄各半）随机分为对照组、模型组、电针组和药物组（匹维溴铵，PB），每组10只。采用慢性不可预测温和应激结合番泻叶溶液灌胃法建立IBS-D模型。电针（2Hz/15Hz，0.1-1mA）交替刺激单侧“足三里”（ST36）、“天枢”（ST25）、“三阴交”（SP6）和“太冲”（LR3），每次15分钟，每日1次，共14天。药物组大鼠灌胃PB（10mL·kg·d），连续14天。采用插入直肠球囊导管充气（连接血压计）诱导大鼠腹部肌肉强烈收缩使大鼠腹部抬起实验台表面的压力阈值评估内脏敏感性（疼痛）。用腹泻指数评估稀便等级。采用免疫组化法检测结肠组织Claudin-1和Occludin（肠上皮紧密连接蛋白）的表达。用分光光度法检测血浆二胺氧化酶（DAO）活性。
与对照组比较，模型组腹泻指数和血浆DAO活性显著升高（<0.01），而模型组内脏痛阈值、Claudin-1和Occludin表达显著降低（<0.01）。治疗后，电针组和药物组腹泻指数和血浆DAO活性均显著低于模型组（<0.01），内脏痛阈值及Claudin-1和Occludin表达水平明显升高（<0.05，<0.01）。电针组与药物组上述各项指标比较，差异均无统计学意义（>0.05）。
电针可显著改善IBS-D模型大鼠的腹痛和腹泻，这可能与其上调肠上皮紧密连接蛋白Claudin-1和Occludin表达以恢复肠上皮黏膜屏障功能密切相关。
