Plasma clearance and tissue binding of rANP[99-126] and iso-rANP[1-45] in the rat.
Plasma clearance and tissue binding of atrial natriuretic peptide (ANP) and iso-ANP were compared in Inactin-anaesthetized rats. It was found that the plasma half-life of iso-ANP was comparable to ANP. Appearance of trichloroacetic acid-soluble radioactivity of iso-ANP in the plasma was considerably slower than that of ANP, suggesting that the metabolic process of these two peptides may be different. Although the binding distribution of these two peptides was similar, the total binding of iso-ANP to organs other than the kidney was much lower. The kidney, lung, heart and adrenal gland appeared to be major target organs for iso-ANP. Autoradiography showed that iso-ANP bound specifically to the renal glomerulus and proximal part of the proximal tubule. This latter binding site in the kidney was not apparent with ANP, suggesting that iso-ANP may exerts its physiological action at different sites in this organ.
Pang
S C
SC
Department of Anatomy, Queen's University, Kingston, Ontario, Canada.
Sarda
I R
IR
Wigle
D A
DA
Zhou
Z J
ZJ
Jennings
D B
DB
Flynn
T G
TG
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000493:pharmacokinetics*; D004232:Diuretics / Q000378:metabolism*; D007687:Kidney Tubules, Proximal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008657:Metabolic Clearance Rate; D009928:Organ Specificity; D010446:Peptide Fragments / Q000097:blood / Q000493:pharmacokinetics*; D051381:Rats; D011919:Rats, Inbred Strains; D017461:Receptors, Atrial Natriuretic Factor; D011956:Receptors, Cell Surface / Q000378:metabolism
D004232:Diuretics; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; C062794:iso-atrial natriuretic peptide; D009320:Atrial Natriuretic Factor; D017461:Receptors, Atrial Natriuretic Factor