Methyl arachidonyl fluorophosphonate (MAFP) is a selective, active-site directed, irreversible inhibitor of cPLA2 and iPLA2. It inhibits A23187-induced arachidonic acid release from human platelets with an IC50 value of 0.6 μM. The IC50 value for inhibition of iPLA2 from P388D1 cells is 0.5 μM. MAFP is a potent inhibitor of fatty acid amide hydrolase, exhibiting an IC50 value of 2.5 nM. MAFP also binds to the CB1 receptor in rat brain membrane preparations. The IC50 values for MAFP and arachidonyl ethanolamide in this assay are 20 and 40 nM, respectively.
