Dose-dependent effects of duodenal and distal ileal infusions of
glucose and oleic acid on meal patterns in rats.
Woltman, Todd, and Roger Reidelberger.
Veterans Administration Medical Center, Omaha, NE 68105 and
Department of Biomedical Sciences, Creighton University School of
Medicine, Omaha, NE 68178
APStracts 2:0038R, 1995.
The mechanisms mediating the anorexic effects of nutrients in the
proximal and distal small intestine are not clearly understood. We
determined the dose-dependent effects of duodenal and distal ileal
infusions of glucose and oleic acid on meal patterns in ad libitum
feeding rats. Rats with cannulas in both the duodenum and ileum
received a 2-h infusion of glucose (0, 800, 1600, 3200, 6400 or
12,800 [mu]mol/h) or oleic acid (0, 48, 240, 640 or 1280 [mu]mol/h) into
the duodenum or ileum at the start of the dark period, and meal
patterns were monitored for 4 h. Cumulative food intake was inhibited
dose-dependently by ileal as well as duodenal infusion of both
glucose and oleic acid. Ileal glucose was more inhibitory than
duodenal glucose, while duodenal oleic acid was more inhibitory than
ileal oleic acid. Duodenal glucose and oleic acid inhibited feeding
by decreasing meal frequency; ileal oleic acid decreased only meal
size, while ileal glucose reduced both meal size and frequency. We
interpret these results to suggest that ileal oleic acid and glucose
suppress feeding by different mechanisms, and that these mechanisms
differ from those mediating the anorexic responses to oleic acid and
glucose in the duodenum.
Received 11 October 1994; accepted in final form 30 January 1995.
APS Manuscript Number R592-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 25 February 1995.