title: Characterization of a high affinity piretanide receptor on kidney membranes.
abstract: The tritiated loop diuretic, piretanide, is a useful ligand for specific diuretic receptors which are present in the plasma membranes of renal medullary cells. Its high specific activity (30 Ci X mmol-1) made it possible to demonstrate the existence of a high affinity receptor (Kd approximately 5 nM) and a binding site with low affinity. High affinity binding is saturable, reversible and displaceable by a number of non-radioactive loop diuretics. Structural analogues, devoid of diuretic activity, do not displace piretanide binding. No specific binding occurs in liver or spleen membranes.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D002462:Cell Membrane / Q000378:metabolism; D004232:Diuretics / Q000378:metabolism*; D004285:Dogs; D066298:In Vitro Techniques; D007668:Kidney / Q000378:metabolism*; D007679:Kidney Medulla / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D008297:Male; D011955:Receptors, Drug / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism; D013449:Sulfonamides / Q000378:metabolism*
chemical_list: D004232:Diuretics; D011955:Receptors, Drug; D013449:Sulfonamides; C015451:piretanide