Specific, high affinity atrial natriuretic factor (ANF) binding sites were identified and localized by autoradiographic techniques in peripheral tissues of the guinea pig, rat, and human. In the guinea pig kidney, high concentrations of ANF binding sites were located in the glomerular apparatus, outer medulla, and small renal arteries. Other peripheral tissues containing ANF binding sites included the zona glomerulosa of the adrenal cortex, the smooth muscle layer of the aorta and gallbladder, the lung parenchyma, the posterior lobe of the pituitary, the ciliary body of the eye, and the leptomeninges and choroid plexus of the brain. The distribution of ANF binding sites in the rat and human kidney was nearly identical to those seen in the guinea pig kidney; high concentrations were present in the glomerular apparatus, outer medulla, and small renal arteries. These results are consistent with earlier physiological and pharmacological studies that suggested that ANF plays a functional role in the regulation of extracellular fluid volume and blood pressure. There appears to be little species variation in the location and concentration of renal ANF binding sites, suggesting that, at least in the kidney, the result in experimental animals are relevant to the actions of ANF in humans. The finding that ANF binding sites were stable and present in high concentrations in human postmortem kidneys further suggest that these tissues may be amenable to testing for the involvement of ANF receptor dysfunction in diseases such as hypertension and congestive heart failure.
ASJC Scopus subject areas
- Internal Medicine