Characterization and tissue distribution of H3 histamine receptors in guinea pigs by N alpha-methylhistamine.
We have used [3H]N alpha-methylhistamine to characterize H3-binding in the guinea pig brain and to study its tissue distribution. Kinetic and equilibrium binding experiments indicate a single class of high affinity sites in membranes isolated from guinea pig brain tissue (Kd = 0.4 nM, Bmax = 41 fmol/mg of protein). Competition binding experiments have confirmed that this ligand associates with H3-receptors and, under the conditions used in these experiments, does not bind to H1- or H2-receptors. Although there was some binding in the ileum and large intestine, H3-binding was found primarily in the central nervous system.
Korte
A
A
Schering-Plough Research, Department of Allergy and Immunology, Bloomfield, New Jersey 07003.
Myers
J
J
Shih
N Y
NY
Egan
R W
RW
Clark
M A
MA
D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism; D006168:Guinea Pigs; D007700:Kinetics; D008761:Methylhistamines / Q000378:metabolism*; D011968:Receptors, Histamine / Q000378:metabolism*; D011969:Receptors, Histamine H1 / Q000378:metabolism; D011970:Receptors, Histamine H2 / Q000378:metabolism; D018100:Receptors, Histamine H3
D008761:Methylhistamines; D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D018100:Receptors, Histamine H3