Histamine H1 receptors identified in mammalian brain membranes with [3H]mepyramine.
The antihistamine [3H]mepyramine binds to H1 histamine receptors in mammalian brain membranes. Potencies of H1 antihistamines at the binding sites correlate with their pharmacological antihistamine effects in the guinea pig ileum. Specific [3H]mepyramine binding is saturable with a dissociation constant of about 4 nM in both equilibrium and kinetic experiments and a density of 10 pmol per gram of whole kinetic experiments and a density of 10 pmol per gram of whole brain. Some tricyclic antidepressants are potent inhibitors of specific [3H]mepyramine binding. Regional variations of [3H]mepyramine binding do not correlate with variations in endogeneous histamine and histidine decarboxylase activity.
D000588:Amines / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D002417:Cattle; D006168:Guinea Pigs; D007700:Kinetics; D008297:Male; D011738:Pyrilamine / Q000378:metabolism; D051381:Rats; D011968:Receptors, Histamine / Q000378:metabolism*; D011969:Receptors, Histamine H1 / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013570:Synaptic Membranes / Q000378:metabolism
D000588:Amines; D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D011738:Pyrilamine