title: Is histamine an anticonvulsive inhibitory transmitter?
abstract: This study was done to investigate the possible role of histaminergic systems in electroshock seizures. Brain histamine concentrations in rats were elevated by metoprine (i.p.), an inhibitor of histamine-N-methyltransferase. Animals were tested for their response to maximal electroshock (MES) at different times after the injection. Metoprine raised brain histamine concentrations and inhibited maximal hindleg extension after MES in a dose-dependent manner. Sensitivity to seizures correlated inversely with histamine concentrations. These results suggest that histaminergic neurones are involved in mechanisms which inhibit generalizations of epileptic discharges in the brain.
mesh_terms: D000818:Animals; D004597:Electroshock; D005260:Female; D006632:Histamine / Q000502:physiology*; D006637:Histamine N-Methyltransferase / Q000037:antagonists & inhibitors; D008297:Male; D009433:Neural Inhibition; D011739:Pyrimethamine / Q000031:analogs & derivatives*; D051381:Rats; D011919:Rats, Inbred Strains; D012640:Seizures / Q000209:etiology / Q000503:physiopathology*; D009435:Synaptic Transmission
chemical_list: C006308:metoprine; D006632:Histamine; D006637:Histamine N-Methyltransferase; D011739:Pyrimethamine