Format

Send to

Choose Destination
Am J Physiol. 1998 Mar;274(3):E527-33. doi: 10.1152/ajpendo.1998.274.3.E527.

Brown fat is essential for cold-induced thermogenesis but not for obesity resistance in aP2-Ucp mice.

Author information

1
Faculty of Sciences, Charles University, Prague, Czech Republic.

Abstract

The role of brown adipose tissue in total energy balance and cold-induced thermogenesis was studied. Mice expressing mitochondrial uncoupling protein 1 (UCP-1) from the fat-specific aP2 gene promoter (heterozygous and homozygous aP2-Ucp transgenic mice) and their nontransgenic C57BL6/J littermates were used. The transgenic animals are resistant to obesity induced by a high-fat diet, presumably due to ectopic synthesis of UCP-1 in white fat. These animals exhibited atrophy of brown adipose tissue, as indicated by smaller size of brown fat and reduction of its total UCP-1 and DNA contents. Norepinephrine-induced respiration (measured in pentobarbital sodium-anesthetized animals) was decreased proportionally to the dosage of the transgene, and the homozygous (but not heterozygous) transgenic mice exhibited a reduction in their capacity to maintain body temperature in the cold. Our results indicate that the role of brown fat in cold-induced thermogenesis cannot be substituted by increased energy expenditure in other tissues.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center