Rat brain concentrations of 5-hydroxytryptamine following acute and chronic administration of MAO-inhibiting antidepressants.
Groups of male Sprague-Dawley rats were injected once daily with phenelzine (15 mg/kg) or tranylcypromine (10 mg/kg) and killed 6 h after drug administration on days 1, 2, 8 and 19. Brains were analyzed for MAO activity by a radiochemical procedure and for 5-HT concentrations by an electron-capture gas chromatographic procedure. Both drugs affected 5-HT concentrations in a similar manner--a significant increase of 5-HT over control levels by day 1, with levels still increasing between days 8 and 19, having attained concentrations approximately 5 times control values by day 19.
D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects*; D008297:Male; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology*; D010624:Phenelzine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000032:analysis*; D014191:Tranylcypromine / Q000494:pharmacology
D008996:Monoamine Oxidase Inhibitors; D012701:Serotonin; D014191:Tranylcypromine; D010624:Phenelzine