KF 13218

KF 13218 is a potent, selective and long lasting thromboxane B2 (TXB2) synthase inhibitor with an IC₅₀ value of 5.3±1.3 nM. IC50 & Target: Thromboxane B2 (TXB2)^[1] In Vitro: KF 13218 inhibits human and bovine platelet thromboxane synthase with IC₅₀ values of 27±5.8 nM (mean±S.E.M.) and 36±6.9 nM, respectively. KF 13218 does not inhibit cyclooxygenase or 5-lipoxygenase up to a dose of 100 μM and does not antagonize thromboxane A2/prostaglandin H2 receptors. KF 13218 inhibits arachidonic acid-induced thromboxane B2 production by human intact platelets with an IC₅₀ value of 5.3±1.3 nM. The IC₅₀ value of KF 13218 for the intact platelets is about 5 times lower than that for the microsomal enzyme. The inhibition of thromboxane synthase in platelets by KF 13218 is sustained after removal of the extracellular compound^[1]. In Vivo: After oral dosing in rat from 0.03 mg/kg to 3 mg/kg, KF 13218 dose-dependently inhibits the thromboxane B2 production in serum, and the inhibition is retained for 72 h. KF 13218, at a dose of 0.1 mg/kg p.o. prevents mortality induced by sodium arachidonate in rabbit^[1].