Neurochemical and behavioural evidence for mediation of the hyperphagic action of 8-OH-DPAT by 5-HT cell body autoreceptors.
Administration of 60 micrograms/kg s.c. of the 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT), a dose previously shown to cause hyperphagia in satiated rats (but not to cause the 5-HT behavioural syndrome) decreased 5-HIAA and 5-HIAA/5-HT ratio in several brain regions, the most marked effects being in pons + medulla oblongata, a region containing 5-HT cell bodies and ascending 5-HT axons. Micro-infusion of 8-OH-DPAT (250 and 500 ng) into the dorsal or medial raphe nuclei significantly increased food intake and feeding duration but did not produce the 5-HT behavioural syndrome. Results suggest that 8-OH-DPAT induced hyperphagia is mediated via a agonist action on somatodendritic 5-HT autoreceptors.
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D004435:Eating / Q000187:drug effects; D001068:Feeding and Eating Disorders / Q000139:chemically induced*; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D006963:Hyperphagia / Q000139:chemically induced* / Q000503:physiopathology; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000502:physiology; D012701:Serotonin / Q000378:metabolism; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D009281:Naphthalenes; D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin