STUDIES ON ACH-INDUCED CONTRACTION OF ILEUM IN RATS

This study was aimed at investigation of the stimulus contractility of the ileum and the concentration of plasma digestive hormones, as well as how the nutritional condition of each individual influences such e xercise effects, in order to clarify the mechanisms for the accelerati on of functions of the alimentary system, caused by long-term voluntar y exercise. Rats were divided into three diet groups(10%, 20%, and 40% protein diets) and subdivided into non-exercise (Cont) and exercise ( Ex) groups. Gastric emptying and the apparent absorption ratio of prot ein, as measured 1 hour after administration of a test diet, were appr oximately equal among three Cent-groups and showed no difference betwe en the Cont- and Ex-groups fed a 10% protein diet, but significantly h igher values were observed for the Ex-group than the Cent-group fed 20 % and 40% protein diets. Like gastric emptying and apparent absorption ratio, farce of acetylcholine (ACh)-induced contraction of the ileum was significantly higher only for the 20% Ex- and 40% Ex-groups. On th e other hand, plasma gastrin, secretin and cholecystokinin-pancreozymi ne (CCK-PZ) showed no distinct intergroup change. Based on the present study, it is thought that long-term voluntary exercise under the cond ition of sufficient intake of protein (20%- and 40%-protein diet) acce lerates the movement ability of the stomach and small intestine to inc rease the pace of digestion and absorption. (C) 1998 Elsevier Science Inc.