FIPI

Despite the high clearance of greater than 2 L/h/kg, FIPI shows a half-life of greater than 5 h, a Cmax of greater than 10-fold the ₅₀ versus PLD2, and moderate bioavailability of 18%. FIPI inhibits both PLD1 and PLD2 in a dose-dependent manner, with 50% loss of activity observed at approximately 25 nM. FIPI is not an irreversible suicide inhibitor but neither is it rapidly and completely reverses upon removal of the drug. IPI does not alter PLD subcellular localization, access to PIP2, actin stress fibers, or upstream signaling events. FIPI rescues PLD2-suppressed membrane ruffling and cell spreading. FIPI attenuats the thimerosal-induced PLD activation, and the Hg-induced PLD activation in MAECs in a dose-dependent manner, and the agonist- and oxidant-induced PLD activation in a dose-dependent manner in MAECs.