Skeletal muscle lipids in normal and dystrophic mice

The lipids of muscle from normal and dystrophic mice of the Bar Harbor strain C57BL/6J were investigated with particular reference to the fatty acid composition of the neutral lipids and phospholipids. Triglyceride, which together with cholesterol comprised most of the neutral lipid fraction, showed no significant changes in fatty acid composition. There was no significant change in the amount of total phospholipid phosphorus in dystrophic muscle, but analyses of the levels of individual phospholipids showed a decrease of 9% in phosphatidylcholine. In both phosphatidylcholine and ethanolamine phosphoglyceride, large decreases were observed in the proportion of the fatty acid 16:0, while 18:0 and 18:1 increased significantly. In phosphatidylcholine 18:2 also increased, and a decrease occurred in 22:6 in ethanolamine phosphoglyceride. Sphingomyelin showed increases in 16:0, 23:0 and 24:1 and decreases in 18:0 and 18:1. The other phospholipid fractions showed less remarkable changes, with a significant increase in 18:0 in lysophosphatidylcholine and a decrease in 16:0 in cardiolipin.