Metabolism of adipose tissue: incorporation of isoleucine carbon into lipids by slices of adipose tissue

• Main Authors: D.D. Feller, E. Feist
• Format: Article
• Language: English
• Published: Elsevier 1959-10-01
• Series: Journal of Lipid Research
• Online Access: http://www.sciencedirect.com/science/article/pii/S0022227520390982

Slices from adipose tissue and liver were incubated with uniformly labeled C14-isoleucine and the respiratory carbon dioxide, fatty acids, and nonsaponifiable lipids were isolated and analyzed for radioactivity. Organic acids were qualitatively identified by chromatography and autoradiography. Adipose tissue oxidized isoleucine to carbon dioxide at a rate greater than that of liver. Conversion to nonsaponifiable lipids was small for both tissues. Recovery of C14 from isoleucine C14 in fatty acids of adipose tissue was 50 to 100 times greater than recovery in liver slices. C14 was recovered in acetate, propionate, methylmalonate, and α-methylacetoacetate in adipose tissue after incubation with isoleucine. The role of acetate, propionate, methylmalonate, α-methylacetoacetate, and isoleucine in biosynthesis of fatty acids in adipose tissue is discussed.