AJP - Regulatory, Integrative and Comparative Physiology, Vol 256, Issue 5 1142-R1147, Copyright © 1989 by American Physiological Society
Postabsorptive glucose decreases excitatory effects of taste on ingestion
M. Bedard and H. P. Weingarten
Department of Psychology, McMaster University, Hamilton, Ontario, Canada.
To test the hypothesis that postprandial rises of plasma glucose attenuate
the motivation derived from positive tastes, we analyzed the effects of
intraperitoneal (ip) injections of glucose on sham feeding, a preparation
in which food intake is motivated primarily by taste sensations. Ip glucose
suppressed sham feeding, with maximal suppressions approximately 42% but
only when glucose was administered contiguous with oropharyngeal
stimulation. The food intake inhibition produced by ip glucose interacted
with palatability; smaller doses of glucose were required to suppress less
concentrated sucrose solutions. Closing the gastric cannula increased the
potency with which ip glucose inhibited eating, suggesting synergy of
postabsorptive glucose with other postgastric satiety signals. The
inhibition of eating produced by ip glucose did not result from malaise.
Thus postabsorptive rises of plasma glucose decrease the ability of taste
cues to drive ingestion and suggest that this phenomenon may contribute to
spontaneous meal termination.
