Depression of rat cerebral cortical neurones by H1 and H2 histamine receptor agonists.
Histamine (H) and H1 agonists 2-pyridylethylamine (PEA) and 2-methylhistamine (2-MH) produced a greater depression of the corticospinal and unidentified rat cerebral cortical neurones than did 4-methylhistamine (4-MH), an H2 agonist. Mepyramine antagonized the effects of 2-MH, PEA and H, and partially antagonized the depression induced by 4-MH. Metiamide and cimetidine, H2 antagonists, blocked 4-MH and H but not 2-MH- and PEA-induced depression. These results indicate that H-induced depression of cortical neurones involves activation of H1 and H2 receptors.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002540:Cerebral Cortex / Q000166:cytology*; D006146:Guanidines / Q000494:pharmacology*; D006632:Histamine / Q000031:analogs & derivatives / Q000502:physiology*; D007093:Imidazoles / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008785:Metiamide / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology; D051381:Rats; D011955:Receptors, Drug / Q000187:drug effects*
D006146:Guanidines; D007093:Imidazoles; D011725:Pyridines; D011955:Receptors, Drug; D008785:Metiamide; D006632:Histamine; C006183:2-(2-aminoethyl)pyridine; D011738:Pyrilamine; D000109:Acetylcholine; D009638:Norepinephrine