Kinetics and distribution of renal receptors of atrial natriuretic factor (ANF) in isolated perfused rat kidney (IK)

Conference · Fri Feb 28 23:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5417863

Suzuki, M; Nussenzveig, D; Almeida, F A; Maack, T

To further investigate the mechanisms of renal action of ANF the authors determined perfusate decay rate (PDR), hydrolysis and specific binding of ANF in IK. /sup 125/I-(1-28)rANF and unlabeled (1-28)rANF (10/sup -12/ to 10/sup -6/M) were added to the perfusate of filtering (F) or non-filtering (NF)IK. At the lowest (ANF), perfusate decay by 20 min perfusion was 54 +/- 2% (n = 7). PDR max (87 +/- 18 fmoles/min/gm kidney) was attained at 10-/sup -9/-10/sup -8/M ANF. PDR was similar in FIK and NFIK. Minimal specific hydrolysis of /sup 125/I-ANF occurred during 50 min perfusion. From 30-50 min perfusate (/sup 125/I-ANF) remained constant in NFIK. At 50 min binding affinity (K/sub d/) and capacity (B/sub max/) were determined in whole kidney (WK), outer cortex (OC), inner cortex (IC), outer medulla (OM) and papilla (P). WK: K = 47 pM, B/sub max/ = 5.6 pmoles/gm tissue: OC: K/sub d/ = 40, B/sub max/ = 7; IC: K = 55, B/sub max/ = 1.8; OM: K/sub d/ = 100, B/sub max/ = 1.8; P: K/sub d/ = 314, B/sub max/ = 3. PDR and binding of ANF were independent of extracellular (Ca). Results demonstrate that IK removes ANF from perfusate in a process which is not dependent on filtration and is due to specific binding of ANF to renal receptors mainly localized in the superficial cortex. Cortical receptors have app. tenfold higher affinity than papillary receptors. Together with previous physiological and autoradiographic data, the results support the view that the full natriuretic effect of administered ANF is due to an increase in GFR and a decrease in papillary hypertonicity.

• Research Organization: Cornell Univ. Medical College, New York, NY
• OSTI ID: 5417863
• Report Number(s): CONF-8604222-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:3; ISSN FEPRA
• Country of Publication: United States
• Language: English

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59 BASIC BIOLOGICAL SCIENCES
AFFINITY
ANIMALS
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
DECOMPOSITION
ELECTRON CAPTURE RADIOISOTOPES
HYDROLYSIS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KIDNEYS
KINETICS
LYSIS
MAMMALS
MEMBRANE PROTEINS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDES
PERFUSED ORGANS
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RODENTS
SOLVOLYSIS
TRACER TECHNIQUES
VERTEBRATES