Similar distribution of [¹²⁵I]sarafotoxin-6b and [¹²⁵I]endothelin-1, -2, -3 binding sites in the human kidney

The distribution of binding sites for ¹²⁵I-labelled endothelins (ET-1, ET-2, ET-3) and sarafotoxin-6b (SRTX-6b) was visualized in human kidneys using autoradiography. The glomeruli, the internal medulla and the renal blood vessels presented the highest levels of labelling while the outer medulla exhibited intermediate and the cortex lower densities of sites. The relative enrichment of binding sites in different renal areas was similar for each peptide, suggesting the existence of a homogeneous population of endothelin/sarafotoxin receptors.