AJP - Gastrointestinal and Liver Physiology, Vol 255, Issue 1 1-G6, Copyright © 1988 by American Physiological Society
Effect of denervation on initiation and coordination of gastroduodenal motility in turkeys
S. B. Chaplin and G. E. Duke
Department of Veterinary Biology, College of Veterinary Medicine, University of Minnesota, St. Paul 55108.
The effect of total extrinsic denervation of the stomach on the rhythmicity
and coordination of the gastroduodenal cycle was determined in domestic
turkeys. The vagus and two gastric branches of the sympathetic nerve were
sectioned at the level of the glandular stomach. Motilities of the
glandular stomach, proximal duodenum, and caudal thin muscle of the
muscular stomach were monitored via implanted strain gauge transducers for
1 h every other day. Denervation had no significant effect on initiation of
contractions or frequency of gastric contractions in fed birds, but fasted
birds whose stomachs were extrinsically denervated exhibited significantly
slower contractions than controls. In addition, denervation uncoupled the
coordination of the duodenal and gastric contractions in the gastroduodenal
cycle. Moreover, birds with extrinsically denervated stomachs exhibited a
cephalic phase of gastric motility that was significantly delayed in onset
compared with controls. These results suggest the existence of both a
neural and endocrine component in the avian gastric response to the sight
of food. Extrinsic input seems to be an important modulator of gastric
motility in birds and is essential for the normal coordination of the
gastroduodenal contraction cycle.
