J Li1, X Liu, P Xie, Q Gu, J Li1, Y Zhang, Z Tang. 1. Department of Gastroenterology, First Teaching Hospital, Beijing University, Beijing 100034, China.
Abstract
OBJECTIVE: To investigate the influence of contraction of isolated colonic smooth muscle and role of guanylin in colonic movement in wrap restraint stress rats. METHODS: By using wrap restraint stress induced defecation rats, the tone of isolated longitudinal and circular colonic muscle strips and guanylin contents in colon and blood were measured by transducer and radioligand binding assay respectively. RESULTS: There were similarities between the intestinal effects of wrap restraint stress in rats and irritable bowel syndrome (IBS) in human. Therefore, wrap restraint stress rat is an appropriate animal model to study stress related intestinal dysfunction. In wrap restraint stress rats, both the tone of smooth muscle and the reaction to K(+), Ca(2+) and acetycholine increased significantly; meanwhile guanylin contents in blood and colon increased also. Trimebutine can decrease the basic tone of smooth muscle and reaction to Ca(2+), K(+) and acetycholine. CONCLUSIONS: The abnormality of colonic smooth muscle contraction is one of the mechanisms in IBS and regulation of colonic smooth muscle contraction is a new method to treat IBS.
OBJECTIVE: To investigate the influence of contraction of isolated colonic smooth muscle and role of guanylin in colonic movement in wrap restraint stress rats. METHODS: By using wrap restraint stress induced defecation rats, the tone of isolated longitudinal and circular colonic muscle strips and guanylin contents in colon and blood were measured by transducer and radioligand binding assay respectively. RESULTS: There were similarities between the intestinal effects of wrap restraint stress in rats and irritable bowel syndrome (IBS) in human. Therefore, wrap restraint stress rat is an appropriate animal model to study stress related intestinal dysfunction. In wrap restraint stress rats, both the tone of smooth muscle and the reaction to K(+), Ca(2+) and acetycholine increased significantly; meanwhile guanylin contents in blood and colon increased also. Trimebutine can decrease the basic tone of smooth muscle and reaction to Ca(2+), K(+) and acetycholine. CONCLUSIONS: The abnormality of colonic smooth muscle contraction is one of the mechanisms in IBS and regulation of colonic smooth muscle contraction is a new method to treat IBS.