Reflex inhibition of gastric motility pathophysiological aspects

Inhibition of gastric motility in response to abdominal trauma was studied in anesthetized cats. Nociceptive stimuli to the gut inhibited the stomach via two different reflex mechanisms. One reflex was strictly spinal and adrenergic inhibiting cholinergic neurons in the stomach. Stimuli to the stomach, small intestine and proximal colon induced stronger adrenergic inhibition than stimuli to distal colon. The second inhibitory mechanism was a vagal nonadrenergic inhibition of gastric tone evoked from all parts of the intestine via spinal afferents. This vagal reflex disturbed gastric electrical control potentials parallel to the motor inhibition. The vagal nonadrenergic and the sympatho-adrenergic reflexes seem to act together in suppressing gastric tone. Adrenal medullary activity was not essential for the gastric response to abdominal trauma.