A-192621 是一种有效的非肽，口服活性，选择性内皮素 B (ETB) 受体拮抗剂，IC50 为 4.5 nM，Ki 为 8.8 nM。A-192621 的选择性比 ETA 高 636 倍 (IC50 为 4280 nM，Ki 为 5600 nM)。A-192621 促进 PASMC 细胞凋亡，并引起动脉血压升高和血浆 ET-1 水平升高。 A-192621 is a potent, nonpeptide, orally active and selective endothelin B (ETB) receptor antagonist with an IC50 of 4.5 nM and a Ki of 8.8 nM. The selectivity of A-192621 is 636-fold higher than ETA (IC50 of 4280 nM and Ki of 5600 nM). A-192621 promotes apoptosis in PASMCs. A-192621 alos causes elevation of arterial blood pressure and an elevation in the plasma ET-1 level.