AJP - Gastrointestinal and Liver Physiology, Vol 238, Issue 6 514-G519, Copyright © 1980 by American Physiological Society
Topical effects of 16,16-dimethyl prostaglandin E2 on gastric blood flow in dogs
L. Y. Cheung
The effects of luminal instillation of 16,16-dimethyl prostaglandin E2
(dmPGE2) on total gastric blood flow and its fractional distribution
between the layers of gastric tissue were determined in exteriorized
segments of the greater curvature of dog stomach. Total gastric blood flow
was measured simultaneously by venous outflow and alpha-labeled
microspheres; both methods correlated well with each other (r = 0.88, P
less than 0.01). In the nonstimulated stomach, dmPGE2 caused an increase in
total gastric blood flow from 4.2 +/- 0.8 to 7.4 +/- 1.2 ml/min (P less
than 0.05). In contrast, dmPGE2 significantly reduced gastric blood flow in
histamine-stimulated stomach (from 14.6 +/- 1.2 to 9.2 +/- 1.0 ml/min; P
less than 0.01). The changes in mucosal blood flow ere proportional to the
alterations in total blood flow because the fractional distribution of
blood flow to the mucosa remained relatively unchanged during dmPGE2
administration. These observations suggest that dmPGE2, a known
vasodilator, induces an increase in gastric blood flow in the resting
stomach, whereas it reduces gastric blood flow in the actively secreting
stomach as a result of secretory inhibition.
