Receptor for endothelin-1. Mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. The rank order of binding affinities for ET-A is: ET1 > ET2 >> ET3 (By similarity). Interacts with HDAC7 and KAT5. Belongs to the G-protein coupled receptor 1 family. Endothelin receptor subfamily. EDNRA sub-subfamily.