EFFECT OF PHOSPHATIDYLETHANOL ON THE FLUI DITY OF PHOSPHOLIPID MEMBRANE AND ITS TOLERANCE TO ETHANOL ATTACK

The effect of phosphatidylethanol on the tolerance of model membrane t o ethanol attack was studied by electron spin resonance using the spin labeled fatty acids with different disposition of DOXYL radical in th e hydrocarbon chain. The stability of lecithin vesicles containing 5 a nd 25 mol % phosphatidylethanol of the same fatty acid composition tow ard the ethanol attack was show to be higher than of the vesicles cons isting of lecithin only. The obtaines data are discussed in the terms of the effect of phosphatidylethanol on the packing of hydrocarbon cha ins in the mixed vesicles. The possible involvement of phosphatidyleth anol in the adaptation of biomembranes to ethanol attack realized by t he activation of cell phospholipase D is speculated.