Evidence that serotonin stimulates a prolactin-releasing factor in the rat.
Methanol extracts of rat plasma resulted in release of prolactin (PRL) from rat hemipituitaries in vitro with a linear log-dose relationship. This prolactin-releasing factor (PRF)-like activity was not altered in plasma from rats treated with bromocryptine or chlorpromazine despite significant suppression and stimulation of plasma PRL levels, respectively. Fluoxetine, a serotonin reuptake inhibitor, plus 5-hydroxytryptophan, the immediate precursor of serotonin, markedly stimulated both plasma PRL and plasma PRF-like activity. Neither fluoxetine, 5-hydroxytryptophan, nor the combination directly stimulated PRL release from rat pituitary tissue in vitro. We conclude that serotonergic stimulation augments PRL release via a PRF.
D000818:Animals; D002746:Chlorpromazine / Q000494:pharmacology; D005473:Fluoxetine / Q000494:pharmacology; D008297:Male; D010902:Pituitary Gland / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism*; D051381:Rats; D012701:Serotonin / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000097:blood*
D005473:Fluoxetine; D012701:Serotonin; D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin; D002746:Chlorpromazine