S18886

The lipid mediator thromboxane A2 (TXA2) plays a key role in platelet aggregation and vascular and bronchial smooth muscle constriction. The actions of TXA2 are mediated by its specific G protein coupled-receptor, referred to as the TXA2 receptor or TP. S18886 is an orally active, long-acting antagonist of the TP receptor with an IC50 value of 16.4 nM.{30021} It inhibits TP receptor-mediated vascular contractions, platelet aggregation, and adhesion and infiltration of monocytes/macrophages in various pre-clinical and clinical models of thrombosis or atherosclerosis.{26175,30019,30020,30018} S18886 is the active isomer of the potent TP receptor antagonist, S18204.{30022} Antagonists of TP receptors have advantages over aspirin (Item No. 70260) as they not only block the effect of TXA2 on platelets, but also inhibit other ligands such as prostaglandin endoperoxides and isoprostanes.{30018,26175}