Abstract
Using 85Sr-labeled microspheres as nonabsorbable markers, the effect of age on gastrointestinal propulsion motility was determined in conscious rats. There was no significant correlation between the gastric emptying rate or the propulsion motility of the small intestine and the age of the rats. The transit time of the intestinal content in the cecum in adult (17-20 mo. old) rats was about 5-fold the value found in weanling (19 day old) rats. The transit time of the large intestine was prolonged by about 70% during the life span investigated.