Binding sites of atrial natriuretic peptide in human renal tissue — Quantification by in vitro receptor autoradiography

Summary Specific binding sites for atrial natriuretic peptide (99–126) in different areas of normal human renal tissue were quantified by in vitro autoradiography. Our data represent the first characterization of ANP binding sites in different structures of the human kidney. Characterization of ANP binding revealed by Scatchard plot analysis a single class of high affinity binding sites in the glomeruli (K_d 0.53±0.11 nM;B_Max 74.4±17.86 fmol/mg protein), the vasculature (K_d 0.18±0.014 nM;B_Max 91.6±25.02 fmol/mg protein), and the medulla (K_d 0.34±0.13 nM;B_Max 106.0±30.61 fmol/mg protein). These sites may play a key role in the actions of the cardiac hormone in human kidney and in the ameliorating effects of ANP in the recovery from acute renal failure.Abbreviations ANP Atrial natriuretic peptide - cGMP Cyclic guanosine monophosphate