Fig. 2.

Ectopic UCP1 expression increases energy expenditure without compromising acute adaptation to cold. A: daily food intake (g·day⁻¹·g body wt⁻¹) over a period of 4 wk; n = 4, means ± SE, Student's t-test. B: measurement of whole body energetics in WT and Tg mice housed at room temperature (22–23°C). V̇o₂ (ml·kg⁻¹·h⁻¹) was measured by indirect calorimetry. V̇o₂ was calculated for both light and dark cycles and was normalized to lean muscle mass. C: V̇o₂ (ml·kg⁻¹·h⁻¹) of WT and Tg mice exposed to cold (4°C) for 24 h. Experiment and data analysis were conducted as described in B; n = 9, means ± SE, Student's t-test.