title: Influence of histamine and related compounds on the hypnotic effect of thiopental in mice.
abstract: Intraventricular injection of histamine (Hi) significantly prolonged thiopental sleeping time at doses of 0.5 microgram or larger. Both 1-methylHi and imidazole-4-acetic acid, however, did not affect thiopental narcosis. Pretreatment with alpha-fluoromethylhistidine diminished the effect of Hi, while histidine, metoprine and quinacrine prolonged thiopental narcosis. Injection with 2-methylHi did not affect thiopental sleeping time, while as in the case of Hi, 4-methylHi augmented the thiopental effect. In addition, H2-receptor blocking agents such as cimetidine, ranitidine and famotidine clearly antagonized Hi-induced prolongation of thiopental narcosis, while pyrilamine and chlorpheniramine had no effect. These results indicate that Hi-induced prolongation of thiopental narcosis appears to be exerted via H2-receptors and is, in some way, related to the Hi content in the brain.
authors.forename: C
authors.initials: C
authors.lastname: Kamei
authors.forename: H
authors.initials: H
authors.lastname: Akahori
authors.forename: K
authors.initials: K
authors.lastname: Tasaka
mesh_terms: D000818:Animals; D004347:Drug Interactions; D006632:Histamine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006635:Histamine H2 Antagonists / Q000494:pharmacology; D006993:Hypnotics and Sedatives; D007276:Injections, Intraventricular; D008297:Male; D008761:Methylhistamines / Q000494:pharmacology; D051379:Mice; D012890:Sleep / Q000187:drug effects; D013874:Thiopental / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D006993:Hypnotics and Sedatives; D008761:Methylhistamines; D006632:Histamine; D013874:Thiopental