Single administration of 5-HT1A agonists decreases 5-HT1A presynaptic, but not postsynaptic receptor-mediated responses: relationship to antidepressant-like action.
The 5-HT1A agonists, 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), buspirone or TVXQ 7821 (ipsapirone) but not the 5-HT1B agonist RU 24969, attenuated the hyperphagic response to 8-OH-DPAT administered on the next day. Attenuation was still apparent on the fifth day after either 8-OH-DPAT or buspirone but not on the tenth day after 8-OH-DPAT administration. The ability of 8-OH-DPAT to reduce raphe 5-HIAA levels was also impaired by previous 8-OH-DPAT treatment. However, the 8-OH-DPAT or 5-methoxy-N,N-dimethyltryptamine-induced 5-HT syndromes were unaltered. The results indicate that a single pretreatment with 5-HT1A agonists rapidly desensitises 5-HT1A presynaptic receptor-mediated responses. This effect may mediate the antidepressant-like action of the drugs in an animal model of depression.
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D004435:Eating / Q000187:drug effects; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D008732:Methoxydimethyltryptamines / Q000494:pharmacology; D011903:Raphe Nuclei / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects*; D012701:Serotonin / Q000378:metabolism / Q000502:physiology*; D013569:Synapses / Q000187:drug effects*; D013764:Tetrahydronaphthalenes / Q000494:pharmacology
D000928:Antidepressive Agents; D008732:Methoxydimethyltryptamines; D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin