TABLE 3.

Increase of metabolic rate and the estimated lipid oxidation of mice during 16.5 min NA-induced thermogenesis

Acclimation Temperature	Genotype	n	Increase of Metabolic Rateab	Estimated Lipid Oxidation of Whole Bodyac	Estimated Lipid Oxidation of Total BATad
30°C	WT	5	9.31 ± 1.1	4.63 ± 0.6	2.55 ± 0.3
	UCP1-KO	7	6.12 ± 0.9*	3.04 ± 0.4*	1.67 ± 0.2*
18°C	WT	12	23.34 ± 0.9	11.60 ± 0.5	6.38 ± 0.3
	UCP1-KO	16	10.30 ± 0.6*	5.12 ± 0.3*	2.82 ± 0.15*
5°C	WT	5	26.98 ± 0.4	13.41 ± 0.2	7.37 ± 0.1
	UCP1-KO	7	9.76 ± 1.2*	4.85 ± 0.6*	2.67 ± 0.3*

Lipid oxidation is calculated from original measurements of oxygen consumption measured via indirect calorimetry. UCP1-KO and WT mice were sequentially acclimated to ambient temperatures of 30°C, 18°C, and 5°C. Values are means ± SEM. Statistically significant differences between the genotypes at each acclimation temperature (P ≤ 0.05) are indicated with *.

^aValues are in milliliters of O₂ per 16.5 min.

^bIncrease of metabolic rate (milliliters of O₂/16.5 min) = amount of consumed oxygen after NA injection in 16.5 min − resting metabolic rate.

^cLipid oxidation whole body = metabolic rate (milliliters of O₂)/A × B. A = 515.2 l O₂/mol palmitate, necessary amount of oxygen for oxidation of 1 mol palmitate; B = 256 g/mol, molar weight of palmitate.

^dLipid oxidation of total BAT = lipid oxidation whole body × 0.55, estimating that BAT contributes 55% of NST [Thurlby and Trayhurn (21)].