Abstract:Objective To study the clinical effect of Cilansetron on treating irritable bowel syndrome (IBS),and investigate its mechanism. Methods Eighty patients with irritable bowel syndrome were randomly divided into two groups: observation group (46 cases, oral Cilansetron 8 mg tid for 6 days) and control group (34 cases, oral vitamin C tablets 50 mg tid for 6 days) between July 2014 and October 2015. The results of treatment were evaluated using the Rome Ⅲcriteria, and the number and degranulation rate of MC in blind back mucosa were measured by immunohistochemical method, and the concentration of 5-HT was measured with the HPLC electrochemical method. The incidences of adverse side effects and the response rates were recorded during the process. Results The value of the efficiency and total efficiency in the observation group were significantly different from those in the control group (p < 0.05). The number of MC and the MC degranulation rate in the observation group were significant lower than those in the control group (p < 0.05), and the concentration of 5-HT in the observation group was also significant higher than that in the control group (p < 0.05). The changes of number of MC, MC degranaulation rate and the concentration of 5-HT in the observation group were more obvious than those in the control group (p < 0.05). Conclusions Cilansetron has significant therapeutic effect on IBS, with reducing the number of ileocecal mucosa MC and the degranulation rate, and regulating the 5-HT signaling pathway to regulate bowel movements.