Influence of cholesterol-enrichment under in vivo and in vitro conditions on the erythrocyte membrane lipids and its deformability.

The cholesterol feeding in rabbits leads to an increase in the levels of cholesterol and phospholipids in plasma and erythrocytes. The increases in cholesterol (C) level is more than that of phospholipids (P) thereby resulting in increase of C/P ratio. The levels of phosphatidylcholine and sphingomyelin are increased in plasma and that of phosphatidylcholine in erythrocytes. Under in vitro conditions the incubation of normal human erythrocytes in cholesterol-enriched plasma (CEP) leads to increase in the cholesterol level, whereas there is no change in phospholipid composition. The deformability of cholesterol-enriched erythrocytes, as measured by their passage time through micropore membranes, under in vivo and in vitro conditions, is significantly decreased.