ANF disappearance and tissue distribution in rats

Journal Article · Sun Dec 31 23:00:00 EST 1989 · American Journal of Physiology; (USA)

OSTI ID:7026893

Widimsky, J Jr; Debinski, W; Kuchel, O; Buu, N T ^[1]

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1. Clinical Research Institute of Montreal, Hotel-Dieu Hospital, Quebec (Canada)

The disappearance of ({sup 125}I)atrial natriuretic factor (ANF; Ser99-Tyr126) from the circulation and its tissue distribution with or without nonlabeled ANF pretreatment were investigated in normotensive Sprague-Dawley rats. Preadministration of the cold peptide increased plasma radioactivity levels for over 8 min following labeled ANF injection but did not change the half-life of circulating labeled ANF. The metabolic clearance rate (MCR) and volume of distribution in the first, second, and steady state phase were significantly decreased after cold ANF pretreatment. Circulating iodo-labeled ANF was taken up by several organs, even by tissues such as fat or bone, but its urinary excretion was very low. The highest uptake was found in the liver (16 +/- 1% of the injected dose), lung (14 +/- 1%), and kidney (12 +/- 1%), diminishing by 21, 89, and 59%, respectively, after cold ANF preinjection. The brain radioactivity was negligible implying an inability of ({sup 125}I)ANF to cross the blood-brain barrier. Our data underscore the importance of the uptake-mediated, cold ANF preadministration suppressible clearance of ANF from the circulation, probably one of its basic elimination mechanisms. The liver, lung, and kidney are probably the most important participants in the MCR of ANF.

• OSTI ID: 7026893
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 258; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL HALF-LIFE
DAYS LIVING RADIOISOTOPES
DISTRIBUTION
ELECTRON CAPTURE RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
METABOLISM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PEPTIDES
PROTEINS
RADIOISOTOPES
RATS
RODENTS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
VERTEBRATES