Patterns of movement of liquids and solids through canine jejunum

The aim of this study was to determine whether interdigestive and digestive motor patterns influence the transit of liquids and solids through the jejunum. In six dogs, a 75-cm segment of jejunum was isolated from the intestinal stream, but myoneural continuity between the segment and the proximal bowel was maintained via a bridge of tunica muscularis. Recording electrodes were implanted on the segment. After recovery, the transit of liquids alone, solids alone, and liquids and solids given together were measured during phases I, II, and III of the interdigestive myoelectric complex and also 30 and 120 min after feeding. During fasting, transit of liquids was most rapid during phase III, slowest in phase I, and intermediate during phase II. After feeding, transit resembled that of phase II of fasting. Transit of spheres was slower, although the patterns of transit resembled those of liquids during fasting and after feeding. Transit of liquids was unaffected by spheres, but transit of spheres was speeded by liquids. It is concluded that changes in interdigestive and digestive motor patterns exerted a marked effect on the pattern of transit of both liquids and solids through the jejunal segment.