Overview
- Breu, V. et al. (1996) FEBS Lett. 383, 37.
Alomone Labs Ro46-8443 inhibits ETB receptor-mediated Ca2+ mobilization in CHO cells.Dose response plot of Ro46-8443 (#R-185) inhibition of the ET-B receptor-mediated, endothelin-1-evoked Ca2+ mobilization (IC50 = 0.88 µM). Cells were loaded with Calcium 6 dye, incubated with Ro46-8443, and stimulated with 30 nM endothelin-1 (EC80). Changes in intracellular Ca2+ levels were detected as changes in maximum relative fluorescence (RLU) using FLIPRTETRA™.
Ro46-8443 is a synthetic compound that acts as a selective and competitive antagonist of the ET-B (endothelin B) receptor, a receptor that belongs to the G-protein coupled receptor (GPCR) superfamily. Ro46-8443 shows a 100-fold selectivity for human ET-B over ET-A receptors and is being used as an important tool for studying the role of ET-B receptors in pathology1. Ro 46-8443 demonstrates IC50 values of 34 nM and 69 nM in competitive binding assays for human ET-B receptors in radiolabeled membranes of Chinese hamster ovary cells and microsomal membranes from human placenta, respectively. The compound also inhibits the binding of selective radiolabeled ET-B agonist Sarafotoxin-S6c to porcine trachea membranes with an IC50 value of 4.9 nM1.
Endothelin receptors are widely distributed in vascular and nonvascular tissues. The ET-B receptor has high and equal affinity for all endothelin isopeptides3. ET-B receptors play an important role in regulating renal function and blood pressure and are expressed in sensory nerves. They are mainly present in medium- and large-sized cell bodies of human trigeminal ganglia3.
