Guanabenz, guanochlor, guanoxan and idazoxan bind with high affinity to non-adrenergic sites in pig kidney membranes.
[3H]Idazoxan is a labelled ligand that is frequently used to study alpha 2-adrenoceptors in the central nervous system. In pig kidney membranes, [3H]idazoxan labelled high-affinity binding sites (Kd = 1.5 nM) that were not alpha 2-adrenoceptors and which recognized clonidine with low affinity. This new class of binding sites was recognized by amiloride derivatives; however, it is not likely that these sites are the well-known targets of amiloride in the kidney: the Na+/H+ exchanger and the epithelium Na+ channel. These binding sites may be the normal target of a series of imidazolidines derivatives (guanabenz, guanochlor, guanoxan), which are known for their antihypertensive properties.
Vigne
P
P
Centre de Biochimie du CNRS, Nice, France.
Lazdunski
M
M
Frelin
C
C
D000584:Amiloride / Q000378:metabolism; D000818:Animals; D000959:Antihypertensive Agents / Q000378:metabolism*; D001667:Binding, Competitive; D002462:Cell Membrane / Q000378:metabolism; D004146:Dioxanes / Q000378:metabolism; D006143:Guanabenz / Q000378:metabolism; D006146:Guanidines / Q000378:metabolism; D019329:Idazoxan; D066298:In Vitro Techniques; D007668:Kidney / Q000378:metabolism*; D011941:Receptors, Adrenergic / Q000378:metabolism; D013552:Swine
D000959:Antihypertensive Agents; D004146:Dioxanes; D006146:Guanidines; D011941:Receptors, Adrenergic; D000584:Amiloride; D006143:Guanabenz; C012340:guanoclor; D019329:Idazoxan