冬凌草片对炎症后肠易激综合征大鼠的治疗作用

Therapeutic Effect of Donglingcao Tablet on Post-inflammatory Irritable Bowel Syndrome in Rats

目的研究冬凌草片对炎症后肠易激综合征(Post-inflammatory Irritable Bowel Syndrome,PI-IBS)大鼠的治疗作用及其机制。方法用2,4,6-三硝基苯磺酸制备PI-IBS大鼠模型,动物灌胃给予冬凌草片0.4,0.8,1.2 g·kg?1·d?1,连续2周。采用腹壁收缩实验测内脏痛阈值;水应激法评价结肠运动;免疫组化法考察嗜铬细胞数;液质联用法测血清素含量,并用免疫印迹法考察色氨酸羟化酶的表达。结果与正常对照组相比,PI-IBS大鼠内脏痛阈值明显降低、结肠排便增多、肠嗜铬细胞增生、色氨酸羟化酶表达增多及血清素含量增高(P<0.05)。冬凌草片高剂量和中剂量给药可显著提高PI-IBS大鼠内脏痛阈值;显著减少结肠排便数量、肠嗜铬细胞数量、血清素含量和色氨酸羟化酶表达(P<0.05)。结论冬凌草片通过减少肠道嗜铬细胞增生和血清素含量治疗PI-IBS大鼠内脏痛及结肠运动障碍。

OBJECTIVE To investigate the therapeutic effect and the underlying mechanism of Donglingcao tablet on post-inflammatory irritable bowel syndrome（PI-IBS） in rats induced by trinitrobenzene sulfonic acid（TNBS）. METHODS PI-IBS rat model was established by TNBS solution intra-colonic administration. PI-IBS rats were orally administered with Donglingcao tablet at the dose of 0.4, 0.8 and 1.2 g·kg-1·d-1 for consecutive 2 weeks. After drugs treatment, visceral pain threshold pressure was measured by abdominal withdrawal reflex test; colon transit was evaluated by water avoidance stress, colonic enterochromaffin cell number was investigated by immunohistochemistry, serotonin content was determined by LC-MS/MS method, and the protein expression of tryptophan hydroxylase（TPH） was tested by Western Blot technique. RESULTS Compared with the normal rats, PI-IBS rats presented reduced visceral pain threshold pressure, increased faecal pellet output, as well as elevated enterochromaffin cell density, serotonin content and TPH expression（P〈0.05）. Compared with PI-IBS rats, high and median dose of Donglingcao tablet treatment significantly increased the pain threshold pressure, markedly reduced the faecal pellet output, and the colonic enterochromaffin cell density as well as serotonin content and TPH expression were all decreased（P〈0.05）. CONCLUSION The analgesic effect and therapeutic effect on colon dysfunction of Donglingcao tablet is associated with the reduced enterochromaffin cell hyperplasia and serotonin content in the colon of PI-IBS rats.