AJP - Gastrointestinal and Liver Physiology, Vol 248, Issue 1 1-G7, Copyright © 1985 by American Physiological Society
Effects of sham feeding, bethanechol, and bombesin on somatostatin release in dogs
J. De Graef and M. C. Woussen-Colle
In seven conscious dogs with esophagostomies and gastric cannulas, the
acid, gastrin, and somatostatinlike immunoreactivity (SLI) responses to
5-min sham feeding with or without pretreatment with atropine sulfate (20
and 100 micrograms/kg) were measured. The responses to bethanechol (100
micrograms X kg-1 X h-1), to bombesin (0.5 micrograms X kg-1 X h-1) with or
without pretreatment with atropine sulfate, and to a combined stimulation
with bethanechol and bombesin were also measured. Sham feeding resulted in
an increase in plasma SLI concentration (basal level, 20.4 +/- 4.2 pg/ml;
maximally stimulated level, 46.8 +/- 5.6 pg/ml; P less than 0.01). After
the injection of atropine the integrated SLI response to sham feeding was
significantly decreased but not suppressed. Infusion of bethanechol did not
alter SLI plasma levels. Bombesin infused alone increased the plasma SLI
concentration (basal level, 15.6 +/- 2.3 pg/ml; maximally stimulated level,
55.6 +/- 10.3 pg/ml; P less than 0.01). The integrated SLI response to
bombesin was significantly decreased by atropine but not significantly
changed by bethanechol. These studies show that sham feeding and bombesin
release somatostatin. They suggest that somatostatin release is largely
under vagal-cholinergic control.
