SCH79797 dihydrochloride is an effective and selective antagonist of protease activated receptor 1 (PAR1) with an IC50 of 70 nM and a Ki of 35 nM. SCH79797 dihydrochloride has antiproliferative and pro-apoptotic effects.

SCH79797 dihydrochloride inhibits thrombin-induced platelet aggregation with an IC50 of 3 μM. In NIH 3T3 cells, SCH79797 dihydrochloride inhibits serum-stimulated activation of p44/p42 mitogen-activated protein kinases (MAPK) at low concentrations and induces apoptosis at higher concentrations[1]. SCH79797 dihydrochloride inhibits high-affinity thrombin receptor-activating peptide ([3H]haTRAP) binding in a competitive manner. SCH79797 dihydrochloride inhibits α-thrombin- and haTRAP-induced aggregation of human platelets. Thrombin produces transient increases in cytosolic free Ca2+ concentration ([Ca2+]i) in hCASMC. SCH79797 dihydrochloride effectively inhibits this increase in [Ca2+]i. SCH79797 dihydrochloride completely inhibits Thrombin- and TK-stimulated [3H]thymidine incorporation [4].

In male Sprague Dawley rats, SCH79797 dihydrochloride (2.5 μg/kg, 10 μg/kg, 25 μg/kg, 50 μg/kg, 100 μg/kg, and 250 μg/kg; i.v.) reduces myocardial necrosis following I/R in the intact rat heart in two rat models of myocardial ischemia/reperfusion (I/R) injury immediately before or during ischemia[3].