SC42619 (free base)

SC42619 free base is a selective platelet thrombin receptor (thrombin receptor) antagonist. SC42619 free base inhibits thrombin-induced platelet aggregation, secretion, calcium influx, and phosphatidic acid phosphorylation, as well as trypsin-induced platelet aggregation. SC42619 free base reduces the content of individual platelets. SC42619 free base inhibits prostacyclin (PGI₂) synthesis in endothelial cells. SC42619 free base can be used for the research of hematological diseases^[2]. In Vitro:SC42619 (0.2-3 mM; 120 s) free base acts as a competitive antagonist of thrombin receptors on washed human platelets, with a pA₂ value of 2.93. Under the condition of 2 nM Thrombin (HY-114164), it completely inhibits Thrombin-induced aggregation, with an IC₅₀ of 425 μM. It also slightly enhances aggregation induced by non-saturating concentrations of U-46619 (HY-108566) in human platelet-rich plasma, and slightly reduces the count of individual platelets, with an EC₅₀ of approximately 0.2 mM^[1].
SC42619 free base competitively inhibits thrombin-induced ATP secretion in washed human platelets^[1].
SC42619 (1 mM; 120 s) free base competitively inhibits Thrombin-induced intracellular Ca²⁺ mobilization when the extracellular Ca²⁺ concentration is <0.1 μM; it non-competitively inhibits Thrombin-induced cytoplasmic Ca²⁺ elevation when the extracellular Ca²⁺ concentration is 1 mM; and it inhibits ADP (HY-W010918)-induced cytoplasmic Ca²⁺ elevation only when the extracellular Ca²⁺ concentration is 1 mM^[1].
SC42619 (5 mM; 120 s) free base inhibits Mn²⁺ influx in washed human platelets induced by Thrombin and ADP^[1].
SC42619 (0-3 mM; 120 s) free base inhibits thrombin-induced ³²P incorporation into phosphatidic acid in the presence of 2.5 nM thrombin, with an IC₅₀ of 0.22 mM^[1].
Co-incubation with SC42619 (5 mM; 30 min) free base and 5 nM Thrombin reduces Thrombin-induced glycoprotein V hydrolysis by approximately 50%^[1].
SC42619 (0.42-5 mM; 2 min) free base potently and selectively inhibits washed human platelet aggregation induced by 2 nM Thrombin, with an IC₅₀ of 0.42 mM^[2].
SC42619 (0.5-5 mM; 2 min) free base selectively inhibits thrombin- and Trypsin (HY-129047)-induced PGI₂ synthesis in human umbilical vein endothelial cells, with an IC₅₀ of 0.5 mM against 3 nM thrombin. It enhances Histamine (HY-B1204)- or Bradykinin (HY-P0206)-induced PGI₂ synthesis, and its inhibitory effect on thrombin-induced synthesis cannot be reversed by increasing the concentration of thrombin^[2].