Motilin regulation of canine interdigestive intestinal motility

Abstract
The objective was to determine whether motilin regulates cyclical interdigestive motility in the jejunum as well as in the duodenum. In four conscious dogs with an intact innervated duodenum, an autotransplanted (extrinsically denervated) 75-cm loop of proximal jejunum, and an autotransplanted,in situ distal jejunum, interdigestive myoelectrical complexes cycled independently in all three regions of small bowel. Plasma concentration of motilin was greater during phase III of the duodenal cycles (304±37 pg/ml) than during phase I (235±37 pg/ml) or phase II (235±39 pg/ml;PP<0.05), but did not alter consistently the interval between phase IIIs in the autotransplanted jejunal segments. Feeding decreased plasma motilin concentration. The data were consistent with motilin regulation of interdigestive motility in intact, innervated canine duodenum but not in extrinsically denervated jejunum.