Effects of stimulation of the small intestine upon the gastric, small intestinal and colonic motility have been studied in dogs. The results are summarized as follows.
1. The movements of the stomach, small intestine, and proximal colon are always inhibited by the distension or the contracture of the muscular coats of the small intestine but no responses are produced by a mechanical or chemical stimulation of the mucosa; and those of the distal
colon are in most cases also inhibited, whereas in rare instances are they augmented. 2. The afferent impulses are transmitted through the great and small splanchnic nerves and the lumbar sympathetic nerves to the inhibitory as
well as the excitatory (pelvic nuclei) centers of the intestinal movements located within the spinal cord, whereas the vagal nuclei remain unaffected. The efferent impulses are transmitted through the thoraco-lumbar sympathetic nerves as well as through the pelvic nerves. The latter are involved in the augmentative effect produced in the distal colon. 3. The threshold producing the extrinsic muscular reflex is higher than that eliciting the intrinsic muscular reflex.</p
