EDN1 and Alzheimer disease: Disease-specific manifestations of ET-1 dysregulation include impaired Aβ clearance and endothelial dysfunction in AD, ischemic penumbral expansion and inverse NVC in stroke/subarachnoid hemorrhage, cortical spreading depolarization in migraine, hyperexcitability in epilepsy, and microvascular degeneration with mitochondrial failure in CSVD and TBI.