Incorporation of acetate-C14 into individual fatty acids of rat liver triglycerides and phospholipids

Control rats, and those made hyperthyroid or hypothyroid by dietary means, showed the same general pattern of C14 incorporation into liver lipid fractions following intraperitoneal injection of C14H3COONa, although the synthesis of phospholipids was apparently decreased in both hyper- and hypothyroid states. Liver triglyceride linoleate was greatly depleted in the hyperthyroid state.The triglycerides and phospholipids together contained 97–99% of the counts from all the principal components recovered chromatographically from liver lipids. A variable fraction of these counts resided in the fatty acid portion. Of the counts in the liver fatty acids, saturated acids had the largest number, both in triglycerides and phospholipids. Monoenoic and tetraenoic acids had comparatively few counts; and dienoic acid only a negligible number.