Changes in membrane lipid content after chronic ethanol administration with respect to fatty acyl compositions and phospholipid type.

Changes in the relative proportions of the phospholipid fatty acids of erythrocyte membranes in mice after chronic ethanol treatment (4.5 g/kg, i.p. twice daily for one week) were shown to vary with the differing control profiles observed. It is suggested that certain changes in membrane lipid composition after ethanol administration may not be interpreted simply in terms of an adaptation to a disordering effect of the drug. The fatty acid changes were, in addition, distributed asymmetrically within the individual phospholipid classes. Depending on the control profile, the effects varied from being mainly in phosphatidylethanolamine (PE; 80%) and phosphatidylserine-inositol (PS + PI; 10%), phospholipids primarily located on the inner half of the membrane bilayer, to being more evenly distributed between PE and phosphatidylcholine (PC) and probably, therefore, between the two halves of the bilayer. Changes in the monounsaturated acid remained primarily with PE, suggesting a specific functional role for this species. The remaining results are discussed in the light of possible effects on cell morphology and their potentially similar consequences of increasing cell volume.