Forinstance, one of the key experimental studies in rats during the 1990s found anincrease in both ET-1 levels and the basal release of ET-1 from mesentericarteries during weeks 5 and 6 (the development of hypertension) in spontaneouslyhypertensive rats (SHRs) compared with age-matched controls. Here, EDN1 is linked to hypertensive disorder.