title: Contribution of the kidney to metabolic clearance of atrial natriuretic peptide.
abstract: To quantify the role of the kidney in whole body metabolic clearance rate (MCR) from plasma of atrial natriuretic peptide (ANP), synthetic alpha-human ANP-(1-28) was infused at 200 ng/min to steady-state conditions in chronically instrumented one-kidney conscious dogs. Clearances were measured in dogs with a normally filtering kidney and they were also measured after the glomerular filtration rate (GFR) was reduced to close to zero by acutely inflating a cuff around the renal artery (RAC), which resulted in minimal urine production and renal blood flow reduction to 59% of the resting level. In normal dogs, MCR was 1,090 +/- 134 ml/min with renal clearance rate (RCR) contributing only 13.9%. After RAC, MCR fell to 864 +/- 151 ml/min, due in part to a fall in RCR (-41.5 +/- 12.9 ml/min), but mostly due to a fall in "rest of the body" (total renal) clearance of ANP. The reduced GFR accounted for virtually all the fall in RCR. Normal plasma ANP half-life was 59.6 +/- 7.9 s. In conclusion, MCR of ANP was very high, approaching the cardiac output, suggesting that most of ANP is cleared in one circulation through peripheral tissues. GFR contributed significantly to RCR (approximately 30%) but the contribution of the kidney to whole body MCR was small relative to rest of the body clearance of ANP.
authors.affiliation: Baker Medical Research Institute, Melbourne, Australia.
authors.forename: R L
authors.initials: RL
authors.lastname: Woods
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D004231:Diuresis / Q000187:drug effects; D004285:Dogs; D005919:Glomerular Filtration Rate; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007668:Kidney / Q000502:physiology*; D008657:Metabolic Clearance Rate; D012016:Reference Values; D012077:Renal Artery / Q000502:physiology
chemical_list: D009320:Atrial Natriuretic Factor