The effect of oxygen exposure on erythrocyte phospholipid composition.

Phospholipids in plasma and erythrocytes of rats exposed to 100% oxygen for 3 days were analyzed. Exposed rats contained lower quantities of several phospholipids in both plasma and erythrocytes than in matched controls. Pronounced decreases were found in phosphatidylcholine and lysophosphatidyl choline. The proportion of disaturated species in erythrocyte phosphatidylcholine was significantly greater after oxygen exposure. There was an increase in percentage of saturated fatty acids with a proportionate decrease in percentage of unsaturated fatty acids. The increase in saturation was associated primarily with palmitate while decreased unsaturation involved primarily linoleic acid. In plasma the proportions of stearic acid increased while those of linoleic, arachidonic and docosahexaenoic acids decreased in phosphatidylcholine. Damage to cell lipids may account for increased hemolysis which occurs after exposure to high oxygen concentrations. Erythrocytes recovered following oxygen exposure contained phospholipid species commonly found in immature red blood cells.