The effect of painless intermittent rectal distension on the rate at which a standard meal passes through the stomach and small intestine was investigated in normal volunteers using noninvasive techniques. Rectal distension significantly retarded the entry of the head of the meal into the cecum and the emptying of the meal from the stomach, although it had no significant effect on basal gastric acid secretion. After administration of the H2-receptor antagonist, ranitidine, there was no significant effect of rectal distension on gastric emptying, but the delay in small bowel transit time induced by rectal distension remained. These data indicate that events occurring in the rectum may influence the function of more proximal regions of the gut.