Volatile anesthetics depress the depolarization-induced cytoplasmic calcium rise in PC 12 cells

In the rat pheochromocytoma cell line PC 12, the effects of four volatile anesthetics (halothane, isoflurane, enflurane, methoxyflurane) on the K+-evoked intracellular calcium [( Ca2+]i) rise were investigated using the Ca2+-sensitive fluorescence dye fura-2. The [Ca2+]i rise was depressed, at clinical concentrations, by all anesthetics with almost identical aqueous IC50 values. The study extends to neuronal cells the observation made previously in cardiac tissue that volatile anesthetics may interfere with Ca2+ fluxes through voltage-gated channels.