Mediation of ACTH and prolactin responses to 5-HTP by 5-HT2 receptors.
Serotonin has a facilitatory role in the role of prolactin and adrenocorticotropin (ACTH) secretion. The serotonin precursor 5-hydroxy-L-tryptophan (5-HTP) dose dependently (30-100 mg/kg i.p.) increased plasma prolactin and ACTH in the male rat. Prolactin and ACTH responses to 5-HTP (100 mg/kg) were attenuated by pretreatment with the non-selective 5-HT receptor antagonist, metergoline (0.5 mg/kg), and by the selective 5-HT2 receptor antagonists, ritanserin (0.4 mg/kg), ketanserin (2.5 mg/kg), ICI (5.0 mg/kg) and spiperone (1.0 mg/kg). The 5-HT1 receptor antagonists, propranolol (40 mg/kg) and pindolol (4.0 mg/kg), failed to antagonize the prolactin and ACTH responses to 5-HTP (100 mg/kg), as did the selective 5-HT3 receptor antagonist, BRL 43694 (1.0 mg/kg). The results suggest that the prolactin and ACTH responses to 5-HTP in the male rat are mediated by 5-HT2 receptors.
Gartside
S E
SE
University of Oxford, Department of Psychiatry, U.K.
Cowen
P J
PJ
D006916:5-Hydroxytryptophan / Q000494:pharmacology*; D000324:Adrenocorticotropic Hormone / Q000037:antagonists & inhibitors / Q000097:blood / Q000378:metabolism*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D008711:Metergoline / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D011388:Prolactin / Q000037:antagonists & inhibitors / Q000097:blood / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects*; D016713:Ritanserin; D012702:Serotonin Antagonists / Q000494:pharmacology; D013134:Spiperone / Q000494:pharmacology
D010880:Piperidines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D016713:Ritanserin; D008711:Metergoline; D013134:Spiperone; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D007650:Ketanserin; D006916:5-Hydroxytryptophan