AJP - Gastrointestinal and Liver Physiology, Vol 255, Issue 2 168-G174, Copyright © 1988 by American Physiological Society
Adenosine plays a role in food-induced jejunal hyperemia
D. R. Sawmiller and C. C. Chou
Department of Physiology, Michigan State University, East Lansing 48824-1101.
The aim of this study is to determine the role of adenosine in postprandial
hyperemia in the jejunum of anesthetized dogs. The effect of two adenosine
antagonists, aminophylline and 8-phenyltheophylline, on the vascular
responses to intra-arterial infusion of adenosine and luminal placement of
food was determined. The effect of aminophylline on the food-induced
hyperemia was found to be dependent on motility. Aminophylline had no
effect on the hyperemia when motility was high but inhibited the hyperemia
when motility was low. Vasodilations produced by intra-arterial infusions
of adenosine, however, were attenuated by aminophylline regardless of the
level of motility. The more potent and specific adenosine antagonist,
8-phenyltheophylline, also inhibited both adenosine- and food-induced
vasodilations. This inhibition occurred whether the intestinal motility was
high or low. In conclusion, adenosine receptor blockade inhibits jejunal
food-induced hyperemia, and adenosine may play a role in the hyperemia. The
effect of aminophylline was complicated by motility.
