EDN1 and type 1 diabetes mellitus: Similarly, the GPCR-mediated vasoconstrictor responses induced by norepinephrine, endothelin-1 (ET-1) and angiotensin II (Ang II) were significantly increased in the mesenteric bed of a rat model of type I diabetes and the treatment of the diabetic animals with AG1478 normalized the altered agonist-induced vasoconstriction responses [37].