EDN1 and Huntington disease: The Rmax to NA (P<0.001, Fig. 1B), ET-1 (P<0.05, Fig. 1D), U46619 (P<0.01, Fig. 2B), Ang II (P<0.0001, Fig. 2D) and vasopressin (P<0.0001, Fig. 2F) were all enhanced in HD patients.