Abstract
Indirect calorimeter is a powerful tool to monitor resting energy metabolism through the measurement of oxygen (O(2)) consumption and carbon dioxide (CO(2)) production. From the measurement of VO(2) and VCO(2), the respiratory exchange ratio (RER) can be calculated to assess energy fuel utilization and energy expenditure (Evan et al., 2012). Previously, indirect calorimeter has been widely used in metabolic disease research in mice to reveal the potential roles of specific genes or treatments in regulating energy metabolism (for example: Bi et al., 2014; Feng et al., 2014). Here, we described a protocol to evaluate the resting energy metabolism of C57BL/6 mice during dark and light cycles using the Oxymax Open Circuit indirect calorimeter.