LAROPIPRANT

Laropiprant is a potent, selective DP receptor antagonist with K _i values of 0.57 nM and 2.95 nM for DP receptor and TP Receptor, respectively.. Laropiprant (1 µM) causes a significant inhibition of the aggregation but still counteractes the pronounced inhibition caused by PGD2 (30 nM) and BW245c (3 nM). Laropiprant blocks DP receptor-dependent increase in VASP phosphorylation, as well as inhibition of P-selectin expression, GPIIb/IIIa activation and in vitro thrombus formation. Laropiprant antagonizes the increased platelet aggregation by TP and EP3 receptor activation. Laropiprant (10 µM) and niacin inhibit in vitro thrombus formation.