VAGAL REFLEX INHIBITION OF MOTILITY IN THE ABOMASAL BODY OF SHEEP BY ANTRAL AND DUODENAL TENSION RECEPTORS

Vagally-mediated regulation of motility in the abomasal body by duoden al and abomasal antral motility was demonstrated in acutely prepared a naesthetized sheep. The enteric plexuses between the abomasal body, an trum and duodenum were interrupted by transection. Antral contractions were more effective than duodenal contractions at causing inhibition of the abomasal body, and antral isometric conditions were more effect ive than antral isotonic conditions. Inhibition of motility in the abo masal body was reduced by unilateral cervical vagotomy, was abolished by bilateral cervical vagotomy, and was reversibly inhibited by cervic al vagus cold block. The demonstration of vagal pathways in abomaso-ab omasal reflexes confirms a functional homology of the mechanisms in th e ruminant and animals with simple forms of stomach.