Fatty Acid Composition of Triglycerides from Adipose Tissue

Abstract

BROWN adipose tissue has recently been shown to be the major site of non-shivering heat production in newborn rabbits¹ and to participate in heat production in the human new-born infant in a cool environment². The major lipid in brown adipose tissue is triglyceride, which is present in numerous small droplets throughout the cytoplasm, and heat is produced by the local oxidation of this triglyceride after lipolysis¹. White adipose tissue contains only a single large fat droplet, is almost entirely triglyceride¹ and its main function is the synthesis and storage of triglycerides and the release of free fatty acids into the blood stream when required. In view of these differences in function we have compared the fatty acid composition of triglycerides from brown and white adipose tissue in new-born and adult rabbits and in samples of brown and white adipose tissue obtained at autopsy in human new-born infants. The fatty acid composition of adipose tissue triglycerides is not significantly different in biopsy and autopsy samples³.