AJP - Gastrointestinal and Liver Physiology, Vol 245, Issue 3 334-G338, Copyright © 1983 by American Physiological Society
Antral control of canine gastric emptying of solids
J. M. Becker and K. A. Kelly
We wondered whether antral mucosal nerves sense the size of particles in
gastric chyme and then activate motor mechanisms that allow only small
particles to empty. Four conscious dogs with duodenal Thomas cannulas were
fed 100 g of bovine liver, half of which was labeled with
cyano[57Co]cobalamin. Duodenal chyme was then collected in 15-min periods
for 5 h and poured through a stack of sieves of decreasing pore size, and
the percentage of radioactivity recovered on each sieve was determined per
hour. Five studies were carried out on each dog before and beginning 2 wk
after antral mucosal neurolysis, during which the antral mucosal nerves
were divided by dissecting the entire antral mucosa circumferentially free
from the surrounding antral muscularis. In the control tests, nearly all
liver (93%) emptied as particles less than 1.4 mm in diameter, but the
percentage emptied as larger particles increased in the 3rd through 5th
postprandial h. After antral mucosal neurolysis, the increase in the
percentage of larger particles emptied occurred sooner and to a greater
extent, but the overall rate of emptying of liver was not changed. We
concluded that antral mucosal nerves have a role in regulating the size of
gastric particles emptied, but a minor one.
