Interrelationships between the major fatty acids present in the lecithin isolated from the plasma of experimental rabbits

Abstract

1. 1. Six groups of rabbits were given for 36 weeks diets containing either 0.2, 0.3, 1.9, 4.9, 5.4 or 10.6% linoleic acid and the fatty acid compositions of the plasma total phospholipid fractions were then determined. 2. 2. Examination of the fatty acid compositions of the total phospholipid fractions revealed that there were significant positive rectilinear relationships between the concentrations of palmitic and oleic acids and between the concentrations of stearic and linoleic acids. Significant negative rectilinear relationships were found between the concentrations of palmitic and stearic acids and between the concentrations of oleic and linoleic acids. 3. 3. The total plasma phospholipid fractions obtained from each group of rabbits were pooled and six samples of pure lecithin were isolated from the pooled plasma phospholipids. The positional distribution of the various fatty acids in the pure lecithin samples was then determined. 4. 4. Significant positive rectilinear relationships were found between the concentration of palmitic acid in the α-position and the concentration of oleic acid in the β-position and between the concentration of stearic acid in the α-position and the concentration of linoleic acid in the β-position. 5. 5. It is suggested that the linoleic acid content of the diet exerts a direct effect on the composition of the fatty acids occupying the β-position and an indirect effect on the composition of the fatty acids occupying the α-position of the plasma lecithin.