title: Interaction of atrial natriuretic peptide with its receptors in bovine lung membranes.
abstract: In bovine lung membranes, atrial natriuretic peptide (ANP) showed temperature-dependent binding to guanylate cyclase-natriuretic peptide receptor (NPR-GC). Photoaffinity labeling of the receptors with 4-azidobenzoyl (AZB)-125I-ANP and competitive binding studies with 125I-ANP, ANP, and atriopeptin I (API) revealed that NPR-GC was detected as the predominant ANP-binding protein at 0 degrees C, whereas at 37 degrees C natriuretic peptide clearance receptor (NPR-C) was detected as the predominant protein. The ratio of NPR-GC and NPR-C was 89:11 at 0 degrees C for 40 min, respectively, whereas 6:94 at 37 degrees C. AZB-125I-ANP bound to NPR-GC dissociated from the binding site within 5 min at 37 degrees C but not at 0 degrees C, whereas ANP bound to NPR-C did not dissociate from the binding site at 0 and 37 degrees C. The dissociated AZB-125I-ANP rapidly rebound to NPR-GC at 37 degrees C but not to NPR-C, and the dissociated NPR-GC was capable of binding. Some AZB-125I-ANP was hydrolyzed by a membrane-bound proteinase(s). Phosphoramidon inhibited the hydrolysis of AZB-125I-ANP. Thus, the dissociated AZB-125I-ANP rebound to NPR-GC and NPR-C. These results suggest that usually intact ANP repeatedly binds to NPR-GC until hydrolysis. Furthermore, the majority of ANP bind to NPR-GC before binding to NPR-C under physiological temperature.
authors.affiliation: Department of Hygiene and Preventive Medicine, University of Shizuoka School of Food and Nutritional Sciences, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Abe
authors.forename: Y
authors.initials: Y
authors.lastname: Arakawa
authors.forename: A K
authors.initials: AK
authors.lastname: Rajasekaran
authors.forename: T H
authors.initials: TH
authors.lastname: Yu
authors.forename: O
authors.initials: O
authors.lastname: Wada
mesh_terms: D000345:Affinity Labels; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000302:isolation & purification / Q000378:metabolism*; D001386:Azides / Q000378:metabolism*; D001667:Binding, Competitive; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D006020:Glycopeptides / Q000494:pharmacology; D007457:Iodine Radioisotopes; D007700:Kinetics; D008168:Lung / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D017461:Receptors, Atrial Natriuretic Factor / Q000302:isolation & purification / Q000378:metabolism*; D013997:Time Factors
chemical_list: D000345:Affinity Labels; D001386:Azides; D006020:Glycopeptides; D007457:Iodine Radioisotopes; D010446:Peptide Fragments; C046452:azidobenzoyl-atrial natriuretic factor; D009320:Atrial Natriuretic Factor; D017461:Receptors, Atrial Natriuretic Factor; C008890:phosphoramidon