Ethanol is a potent stimulator of phosphatidylcholine breakdown in cultured rat hepatocytes

Abstract

Addition of ethanol (17 to 340 mM) to cultured rat hepatocytes stimulated the breakdown of phosphatidylcholine phospholipases D and C as measured by an increase in the rate of release of choline and phosphocholine into 8 medium. The effects of ethanol were mimicked by propanol, dimenthylsulfoxide and to a lesser extent methanol. To magnitude of the stimulation seen with ethanol was equivalent to and additivie to that produced by glucage vasopression, norepinephrine, A23187 or PMA. In contrast, ethanol (340 mM) stimulated PI-specific phospholipa C activity by less than 20%. An equivalent stimulation of PC-specific phospholipase D and C was seen with as little as 20 mM ethanol and a 100% increase was seen with 340 mM ethanol. Ethanol did not significantly affect thev ability of vasopressin, norepinephrine, ATP or A23187 to stimulate PI-specific phospholipase C. It is concluded that while ethanol is only a weak stimulator of PI-specific phospholipase C, it is a potent stimulator of phosphatidyhlcholine breakdown in rat hepatocytes.