Abstract
The 5-HT1A agonist 8-OH-DPAT, at a dose of 30 μg/kg, enhanced the consumption of sweetened wet mash and sweetened milk in non-deprived rats. In partially satiated rats, sensitivity to the hyperphagic effect of 8-OH-DPAT on wet mash intake was substantially increased, so that the minimally effective dose was reduced to 3 μg/kg. Similarly, 8-OH-DPAT was more efficacious in increasing milk intake in satiated rats. Thus, 30 and 40 μg/kg 8-OH-DPAT produced a 4-fold increase of milk intake in completely satiated rats compared to a 2-fold increase in partially satiated animals at a dose of 30 μg/kg. The increased intake of liquid and wet mash diets observed after treatment with low doses of 8-OH-DPAT argues against the involvement of non-specific gnawing in the increased consumption of solid food produced by the drug. Rather, the data suggest that 8-OH-DPAT may specifically stimulate appetite by counteracting a tonic serotonergic inhibition of feeding. The present experiments also showed that 8-OH-DPAT attenuates fenfluramine-induced anorexia which is thought to depend on increased serotonergic neurotransmission.
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Dourish, C.T., Cooper, S.J., Gilbert, F. et al. The 5-HT1A agonist 8-OH-DPAT increases consumption of palatable wet mash and liquid diets in the rat. Psychopharmacology 94, 58–63 (1988). https://doi.org/10.1007/BF00735881
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DOI: https://doi.org/10.1007/BF00735881