TABLE 4.

Indirect calorimetry analysis

Male mice (n = 5; 5–6 months of age) were placed in indirect calorimetry cages and acclimated over at least 2 days, and the measurements were recorded every 20 min over 3 consecutive days. These include oxygen consumption (VO₂), CO₂ production (VCO₂), and heat production. Data were normalized to fat-free lean mass. The respiratory exchange rate (RER) was calculated as VCO₂/VO₂ ratio. Experiments were repeated four times on four different sets of mice. Data presented are cumulative during each of the 12-h light and dark cycles. Values are expressed as mean ± S.E.

	Light		Dark
	Cc1+/+	Cc1−/−	Cc1+/+	Cc1−/−
VO2 (ml/h/kg × 10−4)	15.2 ± 1.07	13.4 ± 0.09	18.4 ± 1.09	16.5 ± 0.59
VCO2 (ml/h/kg × 10−4)	14.4 ± 1.09	12.1 ± 0.31	16.9 ± 1.35	16.4 ± 0.28
RER (VCO2/VO2)	0.95 ± 0.01	0.90 ± 0.02	1.01 ± 0.02	1.00 ± 0.02
Heat (kcal/h/kg × 10−2)	29.3 ± 0.50	22.8 ± 0.29a	36.1 ± 0.88	34.7 ± 0.21

^a p < 0.05 versus Cc1^+/+ mice.