Functional Effects of Endothelin and Regulation of Endothelin Receptors in Isolated Human Nonfailing and Failing Myocardium

Abstract

ET-1 exerts inotropic effects in human myocardium through ETA receptor-mediated increases in myofibrillar Ca2+ responsiveness. In DCM, functional effects of ET-1 are attenuated, but ETA receptor density and ET-1 peptide concentration are increased, indicating an activated local cardiac ET system and possibly a reduced postreceptor signaling efficiency.