痛泻安肠方对腹泻型肠易激综合征模型大鼠结肠TRPV1表达及血浆SP、CGRP含量的影响

目的探讨痛泻安肠方对腹泻型肠易激综合征模型大鼠结肠TRPV1的表达及血清SP、CGRP含量的影响。方法采用冰醋酸灌肠、球囊直肠扩张联合夹尾刺激的方法制备腹泻型肠易激综合征模型,造模成功后,将60只SD大鼠随机分为空白组、模型组、得舒特及痛泻安肠方低、中、高剂量组共6组。观察各组大鼠治疗前后腹壁撤退反射(AWR)评分、粪便Bristol分级评分;采用Western Blot检测结肠TRPV1蛋白表达,采用RealTime PCR检测结肠TRPV1 mRNA的表达,用Elisa测定血清P物质(SP)和降钙素基因相关肽(CGRP)的表达。结果模型组大鼠较空白组内脏敏感性阈值下降(P0.05,P0.01),粪便Bristol分级评分明显升高(P0.01);治疗后,痛泻安肠方低、中、高剂量组和得舒特组大鼠内脏敏感性阈值升高(P0.05,P0.01),粪便Bristol分级评分降低(P0.01),结肠TRPV1蛋白表达下降(P0.05,P0.01),TRPV1 mRNA表达降低(P0.01),血清SP、CGRP水平下降(P0.05,P0.01)。结论痛泻安肠方能降低腹泻型肠易激综合征大鼠内脏高敏感性,其机制可能是通过下调结肠TRPV1蛋白表达,降低结肠TRPV1 mRNA表达,降低血清SP、CGRP水平,上调内脏敏感性而实现的。

Effect of Tongxie Anchang decoction on the expression of TRPV1 and the SP and CGRP of blood plasma in the colon of rats with diarrhea predominant irritable bowel syndrome

Objective To investigate the effect of Tongxie Anchang decoction on the expression of TRPV1 and the content of serum SP and CGRP in rats with diarrhea predominant irritable bowel syndrome. Methods The model of IBS-D was made by intracolonic instillation of acetic acid, balloon rectal dilatation and tail clamping stimulation. After the modeling, 60 SD rats were randomly divided into blank group, model group, intervention group (low-dosage, middle-dosage, high-dosage) and control group. Rats were observed before and after treatment of Abdominal withdrawal reflex (AWR) score and Bristol score; Western Blot was used to detect the expression of TRPV1 in colon, and the expressions of TRPV1mRNA in colon were detected by Real-Time and PCR; The expression of serum substance P(SP) and calcitonin gene related peptide (CGRP) were tested by Elisa. Results Compared with control group, the rats in the model group of visceral sensitivity threshold decreased (P<0.05, P<0.01), fecal Bristol score was significantly increased (P<0.01); After treatment, The visceral sensitivity threshold of rats in low, medium and high dose groups and Dicetel group was increased (P<0.05, P<0.01), fecal Bristol grading score was decrease (P<0.01), colon TRPV1 protein expression decreased (P<0.05, P<0.01), TRPV1mRNA expression decreased (P<0.01),serum levels of SP and CGRP were decreased(P<0.05,P<0.01).Conclusion Tongxie Anchang decoction can reduce visceral hypersensitivity of IBS-D rats, the mechanism may be achieved by downregulating colon TRPV1 protein expression, decreasing colon TRPV1 mRNA expression, decreasing the Serum SP and CGRP levels, and upregulating visceral sensitivity.