ABSTRACT
Endothelin (ET) is a potent vasoconstrictor peptide originally isolated from the culture supernatant of porcine aortic endothelial cells. Intravenous infusion of endothelin to anesthetized dogs increased arterial pressure by increasing peripheral vascular resistance, coronary vascular resistance, and decreasing cardiac output. Renal blood flow and glomerular filtration rate were markedly reduced, accompanied by a reduction in natriuresis and increases in plasma renin activity. ET-converting activity has been detected in both the membranous and cytosolic fractions of cultured porcine, bovine, and human endothelial cells. Investigations of the structural requirements for the metalloproteinase endothelin-converting enzyme (ECE) have indicated that the residues 32–37 of Big ET-1 are important for conversion, while the amino-terminal loop structure appears to interfere with the access of ECE to big ET. The name “endothelin” obviously derives from the endothelial cells from which this peptide was originally isolated.
