A comparison of feeding and locomotion responses to serotonin agonists in three rat strains.

The hyperphagic effects of two selective 5-HT1A agonists (8-OHDPAT and buspirone) in a free feeding paradigm and the locomotor suppressant effect of the serotonin agonist, m-chlorophenylpiperazine (m-CPP) were compared in three different rat strains: Wistar, Sprague-Dawley (SD), and Fawn-Hooded (FH) rats. Administration of various doses of 8-OHDPAT and buspirone produced significant increases in two-hour food intake only in Wistar and SD strains and not in the FH strain. Similarly, various doses of m-CPP produced significant decreases in locomotor activity only in Wistar and SD strains and not in the FH strain. Isolated FH animals gained significantly less body weight relative to both Wistar and SD animals. These findings demonstrate attenuated feeding and behavioral responses to serotonergic agonists in the FH strain relative to both Wistar and SD strains.