Colonic motor response to eating: a manometric investigation in proximal and distal portions of the viscus in man.

The motor response of the human colon to a meal is still poorly characterized. Such data as are available were obtained chiefly for the distal colonic portions with myoelectrical techniques. For these reasons, we investigated proximal and distal colonic motor responses to food ingestion in a rather large group of healthy subjects. Twenty-nine healthy volunteers were studied with a colonoscopically positioned multilumen manometric probe and low-compliance infusion system. Recordings were obtained for 2 h during fasting and for 3 h after the subjects had eaten a 1000-kcal standard mixed meal. During fasting, motility was quite low, and no significant differences between proximal and distal portions were seen. After eating, each portion significantly increased its motor activity throughout the subsequent recording period, but there were differences in the time course in the response to eating for different colonic segments. Proximal portions (especially the transverse colon) had first a sudden maximal increase and then a decrease, whereas the distal ones had a slower and more sustained increase in activity. These findings are of interest, especially for comparison with those of patients with suspected motor dysfunction of the large bowel.