The in vitro incorporation of acetate-1-C14 into individual fatty acids of adipose tissue from young and old rats*

Abstract

The pattern of in vitro incorporation of acetate-l-C14 into the individual fatty acids of adipose tissue from young and old rats was determined. It was found that the proportion of total incorporated radioactivity in the monounsaturated acids was significantly higher in tissues taken from young animals than in tissues taken from old animals. When, however, the rats were fed a fat-free diet, the proportion of monoenes increased in both age groups, and the distribution of acetate-1-C14 in old animals resembled that of the young. The administration of insulin to old animals also led to an increased proportion of the fatty acid radioactivity in palmitoleic and oleic acids. The possible relationship between monoene synthesis in adipose tissue and glucose metabolism, TPNH generation, and the effects of insulin on adipose tissue, were discussed. Evidence was presented demonstrating that the short-chain fatty acids are not synthesized and stored in adipose tissue.