Chronic ethanol effect on the acidic phospholipids of synaptosomes isolated from cerebral cortex of C57BL/6NNIA mice-a comparison with age

A total of six groups of C57BL/6NNIA male mice at 6, 18 and 28 months of age were administered a liquid diet containing either ethanol (8 g/kg body wt/day) or an isocaloric amount of glucose for three weeks. Sixteen hours after the last ethanol feeding, homogenates of cerebral cortices were prepared for isolation of the synaptosome-mitochondrial fraction. Phospholipids were separated by two-dimensional tlc and the level of individual phospholipids was determined by assaying the lipid phosphorus content. Based on protein content, there was a decrease (18%) in the level of phosphatidylserines between samples from 6 and 28 month-old mice; no age difference was observed in other phospholipids. Ethanol consumption resulted in a three-fold increase in poly-phosphoinositide level in the 6 month-old group, but the difference diminished considerably with age. The increase in poly-phosphoinositide level suggests a link between chronic ethanol administration and the receptor-mediated signal transduction mechanism involving phosphoinositide turnover. Results further indicate that animals in the younger age group are more readily influenced by the chronic effect of ethanol than those in the older age group.