title: Histamine H2-receptors in the brain and sleep produced by clonidine.
abstract: Sleep was induced in chicks aged 4-7 days by intravenous injection of clonidine hydrochloride 0.04 mumol/kg. Sleep was not prevented or altered by a preceding intramuscular injection of blockers of histamine H2-receptors which were used in doses (as mumol/kg) of up to 800 (metiamide) and 2400 (cimetidine). Clonidine, therefore, does not cause sleep by stimulating H2-receptors in the brain. The highest dose of cimetidine used had a hypnotic action of its own.
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002645:Chickens; D002927:Cimetidine / Q000494:pharmacology; D003000:Clonidine / Q000494:pharmacology*; D008297:Male; D008785:Metiamide / Q000494:pharmacology; D011968:Receptors, Histamine / Q000187:drug effects*; D011970:Receptors, Histamine H2 / Q000187:drug effects*; D012890:Sleep / Q000187:drug effects*
chemical_list: D011968:Receptors, Histamine; D011970:Receptors, Histamine H2; D008785:Metiamide; D002927:Cimetidine; D003000:Clonidine