The uncoupling protein-1 (UCP1), cloned in 1985 (1– 4) and called UCP until 1997, is an inner mitochondrial membrane protein (5) expressed exclusively in the brown adipocyte (6–8). It dissipates the mitochondrial proton (H) gradient generated by the respiratory chain, producing heat instead of ATP (8, 9). In rodents the brown adipose tissue (BAT) contributes to both the maintenance of body temp...

Inokuma, Ken-ichi, Yuko Okamatsu-Ogura, Asako Omachi, Yukiko Matsushita, Kazuhiro Kimura, Hitoshi Yamashita, and Masayuki Saito. Indispensable role of mitochondrial UCP1 for antiobesity effect of 3-adrenergic stimulation. Am J Physiol Endocrinol Metab 290: E1014–E1021, 2006. First published December 20, 2005; doi:10.1152/ajpendo.00105.2005.—Mitochondrial uncoupling protein-1 (UCP1) has been tho...

The mitochondrial content of skeletal muscles is proportional to activity level, with the assumption that intrinsic mitochondrial function is the same in all muscles. This may not hold true for all muscles. For example, the diaphragm is a constantly active muscle; it is possible that its mitochondria are intrinsically different compared with other muscles. This study tested the hypothesis that ...

Mitochondrial uncoupling protein-1 (UCP1) has been thought to be a key molecule for thermogenesis during cold exposure and spontaneous hyperphagia and thereby in the autonomic regulation of energy expenditure and adiposity. However, UCP1 knockout (KO) mice were reported to be cold intolerant but unexpectedly did not get obese even after hyperphagia, implying that UCP1 may not be involved in the...

The preferential channeling of different fuels to fat and changes in the transcription profile of adipose tissue and skeletal muscle are poorly understood processes involved in the pathogenesis of obesity and insulin resistance. Carbohydrate and lipid metabolism may play relevant roles in this context. Freely moving lean Zucker rats received 3- and 24-h infusions of Intralipid (Pharmacia and Up...

Garcia-Cazarin ML, Gamboa JL, Andrade FH. Rat diaphragm mitochondria have lower intrinsic respiratory rates than mitochondria in limb muscles. Am J Physiol Regul Integr Comp Physiol 300: R1311–R1315, 2011. First published March 9, 2011; doi:10.1152/ajpregu.00203.2010.—The mitochondrial content of skeletal muscles is proportional to activity level, with the assumption that intrinsic mitochondria...

Skeletal muscle is the most abundant tissue in adult body and plays an essential role maintaining heat production for entire body. Recently, muscle-derived non-shivering thermogenesis under cold conditions has received much attention. Zinc-α2-glycoprotein (ZAG) adipokine that was shown to influence energy metabolism adipose tissue. We used ZAG knock-out (ZAG KO) wild-type (WT) mice investigate ...