Effect of ethanol on phospholipid turnover and calcium mobilization in chick embryos

Effects of ethanol on 3H]inositol and 14C]choline incorporation into phosphatidylinositol (PI) and phosphatidylcholine (PC), free intrasynaptosomal Ca2+ (Ca2+]i) and synaptosomal 45Ca2+ uptake, were investigated in the brain and heart of 17-day-old chick embryos to which a 10% ethanol solution had been injected on the 3rd day of embryogenesis. In brain synaptosomes, ethanol increased the incorporation of 3H]inositol and 14C]choline into PI and PC, increased Ca2+]i, and decreased 45Ca2+ uptake. On the other hand, in heart synaptosomal membrane, ethanol decreased the incorporation of 3H]inositol and 14C]choline into PI and PC, decreased Ca2+]i, and increased 45Ca2+ uptake. Ethanol stimulated in vitro 3H]inositol and 14C]choline incorporation into PI and PC in the brain and heart in both the control and ethanol-treated groups. However, addition of ethanol did not affect the release of 45Ca2+ from the synaptosomal membrane of either organ in either group. Addition of ethanol inhibited 45Ca2+ uptake in a dose-dependent manner in the brain but not in the heart. In both organs, there was a relationship between phospholipid turnover and Ca2+]i after ethanol.