Abstract
The mouse is one of the most important model organisms for understanding human genetic function and disease. This includes characterization of the factors that influence energy expenditure and dysregulation of energy balance leading to obesity and its sequelae. Measuring energy metabolism in the mouse presents a challenge because the animals are small, and in this respect it presents similar challenges to measuring energy demands in many other species of small mammal. This paper considers some theoretical, practical, and analytical considerations to be considered when measuring energy expenditure in mice. Theoretically total daily energy expenditure is comprised of several different components: basal or resting expenditure, physical activity, thermoregulation, and the thermic effect of food. Energy expenditure in mice is normally measured using open flow indirect calorimetry apparatus. Two types of system are available - one of which involves a single small Spartan chamber linked to a single analyzer, which is ideal for measuring the individual components of energy demand. The other type of system involves a large chamber which mimics the home cage environment and is generally configured with several chambers/analyzer. These latter systems are ideal for measuring total daily energy expenditure but at present do not allow accurate decomposition of the total expenditure into its components. The greatest analytical challenge for mouse expenditure data is how to account for body size differences between individuals. This has been a matter of some discussion for at least 120 years. The statistically most appropriate approach is to use analysis of covariance with individual aspects of body composition as independent predictors.
| Original language | English |
|---|---|
| Article number | 34 |
| Journal | Frontiers in Physiology |
| Volume | 4 |
| DOIs | |
| Publication status | Published - 14 Mar 2013 |
Bibliographical note
I am grateful to the authors of previously published papers who allowed me to use Figures from their work in this paper. Lobke Vaanholt kindly generated Figure 2 from data previously collected in a study of variation of weight loss on calorie restricted diets. Rachel Sinclair collected the data in Figure 10A as part of her Ph.D. study. Timo Muller kindly provided the data for Figure 10B and Brent Wisse via John Lighton kindly provided the data in Figure 10C. I am grateful to Jon Arch, David Bryant, Matthias Tschoep, Paul Tatner, Henk Visser, Dirkjan Masman, Don Thomas, Ed Melanson, John Lighton, Patrick Even, Eric Ravussin, Ron Khan, Ela Krol, DeHua Wang, Andrew Butler, Alex Johnstone, Diane Jackson, Paul Trayhurn, Lobke Vaanholt, Catherine Hambly, Luiza Duarte, Colin Selman, Lutz Bunger, and Bill Hill for valuable discussions about respirometry methods and analysis. Two anonymous referees made many valuable suggestions to improve the paperKeywords
- energy metabolism
- indirect calorimetry
- mouse models
- energy balance
- obesity
- physical activity
- basal metabolic rate
- energy expenditure
Access to Document
- fphys-04-00034
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