Phencyclidine and the dynamics of mouse brain histamine.
The effects of phencyclidine (PCP) on the dynamics of brain histamine (HA) were examined in the mouse brain. PCP (2-10 mg/kg i.p.) dose-dependently elevated the level of tele-methylhistamine (t-MH), a predominant metabolite of brain HA, without altering the HA level. PCP also enhanced the accumulation of t-MH after administration of pargyline hydrochloride (80 mg/kg i.p.). PCP at 5 mg/kg facilitated the HA depletion produced by (S)-alpha-fluoromethylhistidine markedly (50 mg/kg i.v.), a specific inhibitor of histidine decarboxylase. Metoprine (10 mg/kg i.p.), an inhibitor of HA-N-methyltransferase, decreased the t-MH level and increased the HA level. In the metoprine-treated mice, PCP at 10 mg/kg had no significant effect on the t-MH level, whereas it significantly increased the HA level. The increase in the t-MH level after administration of PCP (5 mg/kg) was observed in various brain regions except the pons-medulla oblongata. These results suggest that, in mice, PCP increases the brain HA turn-over possibly by facilitating the release of HA.
D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects*; D006632:Histamine / Q000032:analysis*; D008297:Male; D008761:Methylhistamines / Q000032:analysis; D008762:Methylhistidines / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains; D010622:Phencyclidine / Q000494:pharmacology*; D011188:Potassium / Q000378:metabolism; D011739:Pyrimethamine / Q000031:analogs & derivatives / Q000494:pharmacology; D011968:Receptors, Histamine / Q000187:drug effects
D008761:Methylhistamines; D008762:Methylhistidines; D011968:Receptors, Histamine; C006308:metoprine; C028309:alpha-fluoromethylhistidine; D006632:Histamine; D010622:Phencyclidine; D011188:Potassium; D011739:Pyrimethamine