Erythrocyte membrane in rats fed high erucic acid-containing mustard oil: Osmotic fragility, lipid composition, and (Na +, K +)- and (Ca 2+, Mg 2+)-ATPases

Erythrocyte hemolytic properties, cholesterol/phospholipid ratios, fatty acid composition, and activities of the membrane-bound enzymes (Na +, K +)- and (Ca 2+, Mg 2+)-ATPase were studied in male and female rats fed low erucic acid rapeseed (LEAR) and high erucic acid mustard oils (HEAM) for a period of 16 months. Rats receiving groudnut oil (GNO) served as controls. Erythrocytes from HEAM-receiving male and female rats showed increased resistance to hypotonic hemolysis. In male rats this was associated with an 85% increase ( P < 0.07) in the cholesterol/phospholipid molar ratio. The fatty acid double-bond index showed an increase in male rats receiving HEAM as well as LEAR oils. In the erythrocytes from female rats, the cholesterol/phospholipid molar ratio and double bond index remained unaffected. Specific activity of ouabain-sensitive (Na +, K +)-ATPase showed a small (+20%) but significant ( P < 0.05) increase in male but not female rats of HEAM group. Total (Na +, K +)-ATPase, ouabain-insensitive component, and (Ca 2+, Mg 2+)-ATPase were not altered in rats receiving LEAR or HEAM.