title: Effects of methysergide and ritanserin on the prolactin and thyrotropin responses to TRH in depressed patients.
abstract: Despite extensive study of the effects of various pharmacological agents on the thyrotropin (TSH) and prolactin (PRL) responses to TRH challenge, the effect of serotoninergic agents remains inconclusive. We studied the effect of the serotonin antagonists methysergide (non-selective 5-HT1/5-HT2 blocker with dopaminergic properties) and ritanserin (selective 5-HT2 blocker) on the TSH and PRL responses to TRH stimulation in two groups of medication-free female depressed patients in a double-blind, within-subject design. Methysergide was found to decrease significantly the PRL response to TRH, while ritanserin had no effect. Neither compound influenced the TSH response. Results suggest that 5-HT2 mechanisms do not mediate the PRL and TSH responses to TRH challenge in depression. The reduction in PRL observed after methysergide is probably due to either 5-HT1 or dopaminergic mechanisms.
authors.affiliation: Department of Psychiatry, Athens University Medical School, Greece.
authors.forename: Y G
authors.initials: YG
authors.lastname: Papakostas
authors.forename: M
authors.initials: M
authors.lastname: Markianos
authors.forename: G N
authors.initials: GN
authors.lastname: Papadimitriou
authors.forename: I M
authors.initials: IM
authors.lastname: Zervas
authors.forename: C N
authors.initials: CN
authors.lastname: Stefanis
mesh_terms: D000368:Aged; D003863:Depression; D005260:Female; D006801:Humans; D008784:Methysergide / Q000494:pharmacology*; D008875:Middle Aged; D011388:Prolactin / Q000378:metabolism; D016713:Ritanserin / Q000494:pharmacology*; D013972:Thyrotropin / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone
chemical_list: D016713:Ritanserin; D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin; D013972:Thyrotropin; D008784:Methysergide