ABSTRACT
White adipose tissue can act as a mechanical buffer to protect delicate internal organs and to provide thermal insulation but it is its role as an energy store that particularly interests the biochemist and the physician. In essence, its role is the storage of long chain fatty acids as triacylglycerols in times of energy surfeit and the mobilization of fatty acids out of this triacylglycerol store in times of anticipated or actual energy demand. A certain amount of general "turnover" of these stores probably occurs continuously but whether the tissue is bringing about net deposition or net mobilization will depend upon the relative activities of the lipolytic and esterification processes, the phosphohydrolase playing a prominent role in the latter. Brown adipose tissue is mainly located in the interscapular and axillary regions. Nonshivering thermogenesis in brown adipose tissue is particularly important in mammals during early postnatal life, during cold exposure, and on arousal from hibernation.
