BQ123 + BQ788

BQ123 + BQ788 is a combination of two selective endothelin receptor antagonists used primarily in research to study and inhibit the effects of endothelin-1 (ET-1), a potent vasoconstrictor peptide. - **BQ-123** is a selective antagonist of the endothelin A (ETA) receptor, which mediates vasoconstriction and cell proliferation. It blocks ET-1 binding to ETA receptors, leading to vasodilation. - **BQ-788** is a highly selective antagonist of the endothelin B (ETB) receptor, competitively inhibiting ET-1 binding with high potency (IC50 ~1.2 nM for ETB). It inhibits ETB-mediated vasoconstriction, bronchoconstriction, and cell proliferation. The combination synergistically inhibits ET-1-induced contraction more completely than either agent alone by blocking both ETA and ETB receptors simultaneously. This dual blockade is necessary because activation of either receptor subtype alone can cause full vasoconstriction in some vascular beds such as rabbit pulmonary artery. These compounds are mainly used in experimental settings to investigate cardiovascular physiology/pathophysiology including pulmonary hypertension, renal function alterations in chronic renal failure, coronary heart disease models, and tumor vessel regulation.

Other names

Endothelin receptor antagonists combination