Overview
- Balwierczak, J.L. et al. (1995) J. Cardiovasc. Pharmacol. 26, S393.
- Webb, R.L. et al (1995) J. Cardiovasc. Pharmacol. 26, S389.
- Alomone Labs IRL 2500 inhibits ETB receptor-mediated Ca2+ mobilization in CHO cells.Dose response plot of IRL 2500 (#I-190) inhibition of the ETB receptor-mediated, endothelin-1-evoked Ca2+ mobilization (IC50 = 179.6 nM). Cells were loaded with Calcium 6 dye, incubated with IRL 2500, and stimulated with 30 nM endothelin-1 (EC80). Changes in intracellular Ca2+ levels were detected as changes in maximum relative fluorescence (RLU) using FLIPRTETRA™.
IRL 2500 is a synthetic compound that acts as a potent and selective antagonist of ET-B (endothelin B) receptor, a receptor that belongs to the G protein-coupled receptors (GPCR).
IRL 2500 is more selective for human ET-B over ET-A receptor and can be used to delineate responses mediated by the ETB receptor1. IRL 2500 demonstrates IC50 values of 1.3 nM and 94 nM for human ETB and ETA receptor expressed in transfected Chinese hamster ovary cells respectively1.
Several in vitro studies have shown that IRL 2500 can inhibit the sarafotoxin S6c-mediated contraction of the dog saphenous vein and the sarafotoxin S6c-induced relaxation of the preconstricted rabbit mesenteric artery. IRL 2500 also attenuates the IRL 1620-mediated increase in renal vascular resistance and decrease in arterial pressure in the anesthetized rat1,2.
Endothelin receptors are widely distributed in vascular and nonvascular tissues. ET-B receptor has equally high 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 ganglia4.