Endothelin 1 (ET-1), also known as preproendothelin-1 (PPET1), is a protein that in humans is encoded by the EDN1 gene. ET-1 is one of three isoforms of human endothelin. Endothelins can affect the central nervous system and neuronal excitability, and they elicit potent vasoconstrictor action. ET-1 has been implicated in the development and progression of vascular disorders such as atherosclerosis and hypertension. Endothelial cells upregulate ET-1 in response to hypoxia, oxidized LDL, pro-inflammatory cytokines, and bacterial toxins. Initial studies on the ET-1 promoter provided some of the earliest mechanistic insight into endothelial-specific gene regulation. Numerous studies have since provided valuable insight into ET-1 promoter regulation under basal and activated cellular states.
