Changes in lipid composition and osmotic fragility of erythrocytes of hamster induced by heat exposure

In attempting to explain the increased osmotic fragility of hamster erythrocytes following a prolonged exposure of the animals to an elevated ambient temperature, the lipids and fatty acids of the red blood cells were studied. The heat exposure of the hamsters resulted in a lower cholesterol/phospholipids ratio, a lower content of phosphatidyl choline and sphingomyelin and a higher content of phosphatidyl ethanolamine and phosphatidyl serine. In erythrocytes of control hamsters, the major fatty acid of phosphatidyl choline, phosphatidyl serine and sphingomyelin is linolenic acid, while it is palmitic acid in the erythrocytes of the heat-exposed animals. Each of these modifications in the lipid profile of the red blood cells may contribute to the difference in osmotic fragility between the two groups of hamsters.