Impromidine-induced hypothermia in rats: effect of cimetidine and mianserine.
Impromidine, a highly potent histamine H2-receptor agonist, given i.v. at doses of 3.1-62 nmole, induced a dose-dependent hypothermia in the rat with a maximal effect after 15 min. Cimetidine, an H2-receptor antagonist, having no effect when administered alone, antagonized the hypothermic action of impromidine. Two antiserotoninergic agents, p-chlorophenylalanine and metergoline, and chronic treatment with an antidepressant mianserine reduced the impromidine-induced hypothermia. It is suggested that the impromidine-induced hypothermia is an H2-receptor-mediated phenomenon, and the antagonizing effect of mianserine is related to serotonin receptor blocking activity of the drug rather than to its direct H2-receptor antagonism.
D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D002927:Cimetidine / Q000494:pharmacology*; D003984:Dibenzazepines / Q000494:pharmacology*; D004298:Dopamine / Q000502:physiology; D006146:Guanidines / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology*; D017446:Impromidine; D008297:Male; D008803:Mianserin / Q000494:pharmacology*; D010275:Parasympathetic Nervous System / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D011968:Receptors, Histamine / Q000187:drug effects*; D011970:Receptors, Histamine H2 / Q000187:drug effects*; D012701:Serotonin / Q000502:physiology; D013564:Sympathetic Nervous System / Q000187:drug effects; D009435:Synaptic Transmission / Q000187:drug effects
D003984:Dibenzazepines; D006146:Guanidines; D007093:Imidazoles; D011968:Receptors, Histamine; D011970:Receptors, Histamine H2; D008803:Mianserin; D012701:Serotonin; D002927:Cimetidine; D017446:Impromidine; D004298:Dopamine