title: Fatty acid synthesis in brown adipose tissue in relation to whole body synthesis in the cold-acclimated golden hamster (Mesocricetus auratus).
abstract: The synthesis of fatty acids has been measured in vivo with 3H2O in brown adipose tissue, the liver, white adipose tissue and the 'carcass' of cold-acclimated (4 degrees C) golden hamsters (Mesocricetus auratus), and the results compared with those of warm-acclimated (30 degrees C) animals. In warm-acclimated hamsters the highest rate of synthesis was found in the liver, which accounted for more than a quarter of the total body synthesis. Cold-acclimation led to an almost 3-fold increase in whole-body fatty acid synthesis, compared to warm-acclimated animals, and this resulted from increases in all the individual tissues examined, particularly in brown adipose tissue. In cold-acclimated hamsters the rate of synthesis appeared to be similar in brown adipose tissue and the liver. However, studies with Triton WR 1339 suggested that at least one-half of the apparent synthesis in brown adipose tissue resulted from the rapid incorporation into the tissue of fatty acids synthesised elsewhere. On a whole-body basis, the liver made a much greater contribution than brown adipose tissue to total fatty acid synthesis in cold-acclimated hamsters; this is in marked contrast to the relative importance of these two tissues in cold-acclimated rats and mice. It is concluded that in the hamster, an animal widely used for studying the mechanisms of non-shivering thermogenesis in brown adipose tissue, the fatty acids utilised for generating thermoregulatory heat are synthesised principally in tissues other than brown adipose tissue.
mesh_terms: D000064:Acclimatization; D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism*; D002001:Adipose Tissue, Brown / Q000378:metabolism*; D000818:Animals; D003080:Cold Temperature; D006224:Cricetinae; D005227:Fatty Acids / Q000096:biosynthesis*; D008099:Liver / Q000378:metabolism; D008297:Male; D008647:Mesocricetus; D011092:Polyethylene Glycols / Q000494:pharmacology
chemical_list: D005227:Fatty Acids; D011092:Polyethylene Glycols; C016811:tyloxapol