FATTY-ACID PROFILES OF PHOSPHOLIPIDS IN BROWN ADIPOSE-TISSUE FROM RATS DURING COLD-ACCLIMATION AND REPETITIVE INTERMITTENT IMMOBILIZATION -WITH SPECIAL REFERENCE TO DOCOSAHEXAENOIC ACID

The effects of cold acclimation and repetitive intermittent immobiliza tion were examined on fatty acid (FA) compositions in phospholipids of rat interscapular brown adipose tissue (BAT) and plasma. As previousl y reported, cold acclimation and intermittent immobilization increased the degree of unsaturation as a whole in FAs of BAT but not in plasma . N-3 polyunsaturated docosahexaenoic acid (22-6; DHA) decreased in co ld acclimation but increased in intermittent immobilization in phospho lipids of BAT. DHA was decreased in phospholipids of plasma in both gr oups. Considering our previous findings that the in vitro thermogenic response of BAT was suppressed in cold acclimation and enhanced in int ermittent immobilization, it ws inferred that DHA in BAT is involved i n the regulation of thermogenic function of this tissue.