Comparative study of the effect of ethanol on the fluidity of subcellular hepatic membranes.

The aim of this study has been to compare the effects of chronic ethanol administration on the lipid composition and fluidity of chick-liver microsomes and mitochondria. Cholesterol levels were increased only in microsomal membranes whilst the fatty-acid profiles were considerably altered in the major phospholipids in both membranes. By using fluorescence polarization we found that ethanol produces a disorganisation of acyl chains in the core of microsomes and mitochondria and consequently causes higher fluidity. In addition, opposite changes were induced by ethanol in the polar region of the microsomes, inducing a more rigid area in the membrane.