Abstract
These studies investigated the involvement of the 5-HT1A receptor in mediatingd-fenfluramine-induced anorexia in the rat. Non-deprived,d-fenfluramine-treated (3.0 mg/kg) rats consumed a reduced amount of a palatable wet mash and showed a temporal advance in the behavioural sequence consistent with satiety. Thus, rats treated withd-fenfluramine ceased feeding and began resting before corresponding controls. Pretreatment with the selective 5-HT1A receptor antagonist WAY-100635 (1.0 mg/kg) had no effect on either the reduced mash consumption or behavioural satiety sequence ofd-fenfluramine-treated animals at a dose which was found to attenuate the anorexia induced by the 5-HT1A receptor agonist 8-OH-DPAT (0.5 mg/kg). Pretreatment with the nonselective 5-HT antagonist metergoline (1.0 mg/kg) attenuated thed-fenfluramine-induced reduction of mash consumption and the advanced offset of feeding. Metergoline pretreatment had no effect on the advanced onset of resting observed ind-fenfluramine-treated animals. These data suggest thatd-fenfluramine reduces food intake, perhaps by enhancing satiety, via a mechanism which does not involve the 5-HT1A receptor subtype. The implications of these results to the utility of the behavioural satiety sequence as a measure of postprandial satiety are discussed.
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Vickers, S.P., Clifton, P.G. & Dourish, C.T. Behavioural evidence thatd-fenfluramine-induced anorexia in the rat is not mediated by the 5-HT1A receptor subtype. Psychopharmacology 125, 168–175 (1996). https://doi.org/10.1007/BF02249416
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DOI: https://doi.org/10.1007/BF02249416