Regulation of bile duct motility by vagus and sympathetic nerves in the pigeon.

Effects of stimulation of the vagus and sympathetic nerves on bile duct peristalses were studied in pigeons anesthetized with urethane. Vagus stimulation increased the frequency of peristalses. Atropine, hexamethonium and tetrodotoxin abolished this excitatory effect. After atropine, inhibition of peristalses sensitive to tetrodotoxin was produced. Stimulation of sympathetic area in the spinal cord inhibited peristalses. Propranolol converted this effect into an excitatory one, which was abolished by phentolamine. The results suggest that vagal and sympathetic innervations of the bile duct in pigeons are similar to those of the sphincter of Oddi in mammalian species.