PtdIns(4,5)P2 a-fluorovinylphosphate diC8 is a water soluble, synthetic PI(4,5)P2 analog in which the phosphodiester bond has been rendered metabolically stable via the α-fluorovinylphosphonate. P-FV4508 restores the TRPM4 ion channel current at similar concentrations as diC8-PI(4,5)P2.