Lipid composition and synthesis in the muscles of normal and dystrophic chickens.

Abstract

The lipids of the superficial pectoral muscle of 5-week-old normal and dystrophic New Hampshire chickens were fractionated by thin-layer chromatography procedures. Total lipid in the dystrophic muscle was fivefold greater than in normal muscle with the triglycerides 15-fold greater and the phospholipids 1.5-fold greater (wet weight basis). The relative proportions of phospholipids were quite similar except for significantly less phosphatidylcholine and phosphatidic acid in the dystrophic muscle. In another study acetate-2-14C was injected intraperitoneally into normal and dystrophic chickens which were killed at various times up to 7 days after the administration. The dystrophic birds incorporated acetate-2-14C to a greater extent into total lipids, triglycerides, and phospholipids of the muscle than normal chickens. The turnover times for both triglycerides and phospholipids were much greater in dystrophic than in normal chickens with the triglycerides showing a longer time than the phospholipids. In vitro incubation of acetate-2-14C with muscle slices showed a greater rate of incorporation into lipid by dystrophic than by normal muscle. These results indicate that the difference in acetate incorporation between normal and dystrophic muscle was due to metabolism in the muscle itself and not entirely a result of mobilization of lipid from other tissues.