Detection and characterization of 3H-clonidine binding sites in coated vesicles isolated from bovine brain.
The binding of 3H-clonidine to bovine brain coated vesicles was studied. The binding was reversible and saturable. Saturation studies revealed a one-site interaction: Kd was 8.7 nM and Bmax was 24.5 fmol/mg protein. Noradrenaline, yohimbine and phenoxybenzamine displaced 3H-clonidine binding from the binding sites at concentrations of 10(-7)-10(-4) M. The results indicate that the coated vesicles from the bovine cerebral cortex contain 3H-clonidine binding sites comparable to the low affinity sites of alpha 2-adrenergic receptors in bovine brain membranes.
Moroi
K
K
Division of Functional Neurobiology, School of Medicine, Chiba University, Japan.
Kuga
T
T
Kadota
K
K
D000316:Adrenergic alpha-Agonists / Q000378:metabolism; D000317:Adrenergic alpha-Antagonists / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D002417:Cattle; D003000:Clonidine / Q000378:metabolism* / Q000493:pharmacokinetics; D054755:Imidazoline Receptors; D066298:In Vitro Techniques; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism; D018341:Receptors, Adrenergic, alpha-2; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism*; D015016:Yohimbine / Q000494:pharmacology
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D054755:Imidazoline Receptors; D011942:Receptors, Adrenergic, alpha; D018341:Receptors, Adrenergic, alpha-2; D015016:Yohimbine; D003000:Clonidine