Overview
- Winn, M. et al. (1996) J. Med. Chem. 39, 1039.
Alomone Labs Atrasentan inhibits ET-A receptor-mediated Ca2+ mobilization in CHO cells.Dose-response curve of Atrasentan (#A-455) inhibition of ET-A receptor-mediated, endothelin-1-evoked Ca2+ mobilization. IC50 was determined at 0.124 nM. Cells were loaded with Calcium 6 dye, incubated with Atrasentan, and stimulated with 15 nM endothelin-1 (EC80). Changes in intracellular Ca2+ levels were detected as changes in maximum relative fluorescence (RLU) using FLIPRTETRA™.
Atrasentan (A-127722) is a synthetic compound that acts as a potent and selective antagonist of endothelin A (ET-A) receptor. Atrasentan is highly selective towards ET-A receptor, exhibiting 1000-fold selectivity over ET-B receptors1. It inhibits endothelin-1 radioligand binding with an IC50 value of 0.36 nM and endothelin-1-stimulated phosphoinositol hydrolysis with an IC50 of 0.16 nM1.
ET-A receptors are predominantly detected in peripheral tissues, especially in vascular smooth muscle tissues where they mediate vasoconstriction. They are also expressed in several regions of the brain. The ET-A receptor has high affinity for endothelin-1 and endothelin-2 and relatively low affinity for endothelin-3, while the ET-B receptor has high affinity for all endothelin isopeptides2.
