Intraaccumbens infusions of the GABA, agonist baclofen are known to stimula
te food intake in the rat. The aim of the present study was to evaluate the
effects of baclofen infusion on nonfood-related chewing and on the consump
tion of a palatable fluid. Rats were bilaterally infused with baclofen (188
ng in 1 mu L) or saline, rind tested in a situation in which food was avai
lable in one or two locations and wood blocks might also be present. Baclof
en-infused animals showed no enhancement of chewing directed at the wood bl
ocks, but showed increased food consumption regardless of food location. In
a second, separate test we recorded the microstructural parameters for dri
nking of a palatable glucose/saccharin mixture. Baclofen infusion had no ef
fect on overall intake, although bout size was reduced and the number of bo
uts was increased. These data confirm that baclofen-stimulated food intake
following accumbens infusion is a robust and substantial phenomenon that ap
pears to be selective to solid food. It is likely to result from relatively
direct activation of neural circuits for feeding, rather than an indirect
facilitation consequent upon changes in taste processings, as has been sugg
ested for some other examples of drug-induced hyperphagia. (C) 2000 Elsevie
r Science Inc. All rights reserved.