Energy metabolism
 Whole-body composition using EchoMRI in awake mice
EchoMRI™ provides the most precise measurements of whole-body composition in live mice. Total body fat, lean mass, body fluids, and total body water, are measured in less than 1 minute without the need for anesthesia or sedation, facilitating low-stress longitudinal tracking of small changes in body composition. EchoMRI is suitable for mice up to 100 grams.
A minimum of 5 mice is appropriate for longitudinal studies, whereas 8 to 10 mice are required for a single comparison between groups. An acclimation period may be necessary in the event that mice lose body weight during the transfer to our facility.
Price per mouse : CHF 50.-
References: http://www.echomri.com/about_us.html
Indirect calorimetry
Maintenance of body weight relies on the fine control of the balance between energy intake and energy expenditure. Obesity or leanness results when food intake exceeds or is lower than energy expenditure. Energy can be expended by performing work (e.g. locomotor respiratory and cardiac activities) or producing heat (thermogenesis).
The body has the ability to utilize and transition between various fuels (such as carbohydrate, lipid and proteins), and to transition between these in response to hormonal, chiefly insulin, and substrate signals, as during the fasting to feeding transition. This plasticity can be altered in transgenic mice models, or lost due to obesity and type 2 DM.
The Comprehensive Lab Animal Monitoring System (CLAMS) (Columbus Instruments, Columbus, OH) consists of 8 individual live-in cages for mice that allow automated, non-invasive evaluation of energy intake and energy expenditure, as well as metabolic substrate selection. Each cage is an indirect open circuit calorimeter (Oxymax) that provides measures of oxygen consumption (VO2) and carbon dioxide production (VCO2). The Respiratory Exchange Ratio no-protein (no-protein RER, or respiratory quotient VCO2/VO2), is used to estimate substrate disappearance rates. Heat production is estimated from oxygen consumption and from the RER. The system also concurrently measures food and water consumption, and locomotor activity.
Mice are acclimated to the metabolic cages for 48 hours prior to the experiment. Data are collected for 1 to 3 consecutive 24-hour periods with a 12:12 light:dark cycle.
A minimum of 8 mice per group should be sent to our facility, one week prior to the experiment.
Price per mouse : CHF 60.-
Metabolic Response to Exercise
Exercise is a useful integrated measure of fitness. Changes in exercise capacity are both sensitive and early markers of cardiac and metabolic dysfunction.
Treadmill exercise in the mouse can be used to quantify the capacity for either endurance or high intensity exercise. The challenge can be performed either acutely, or after up to a 10 week training period in order to increase VO2max and mitochondrial density in rodent skeletal muscle.
Indirect calorimetry can be couped to treadmill exercise to describe the metabolic cost of exercise, as well as substrate selection (see indirect calorimetry).
A minimum of 8 mice per group should be sent to our facility, one week prior to the experiment.
Price : please contact us. Given the labo-intensive nature of this technique, applicants will be asked to participate to the experiments.
 Body temperature and spontaneous locomotor activity
Handling and restraint induce stress responses that are highly detrimental to measurements of stress-sensitive physiologic parameters such as body temperature. As differential stress responses between groups cannot be discriminated from innate differences in the measured parameter, artifactual measurements can often lead to erroneous conclusions.
The DSI PhysioTel® telemetry system allows the online monitoring of body temperature and locomotor activity in mice while they move freely within their cages. A miniature radioemitter device is implanted in each animal and does not interfere with normal biological functions, including pregnancy.
A minimum of 8 mice per group should be sent to our facility, one week prior to the experiment.
Price per mouse : CHF 75.-
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