In vivo imaging of small animals, such as mice, makes it possible to expand and to verify results obtained at a cellular level in a system (the whole animal) where supracellular interactions occur. Biologically, interactions can be followed in this way in time and space at the level of the whole organism. This has major benefits for both basic research and pre-clinical studies. Furthermore, since it is non-invasive, it allows assessment of the same animal at different time points and in this way accelerates research and reduces the number of animals employed in the study.
Two imaging technologies are available:
- In Vivo Imaging of fluorescence and bioluminescence:
An IVIS Spectrum instrument is available. This instrument makes it possible to carry out non-invasive longitudinal monitoring of bioluminescent and fluorescent reporters in anaesthetised mice.
- In vivo photoacoustic imaging: a Vevo LAZR instrument with a pulsed laser in the tunable range from 410 to 2400nm is available. This hybrid imaging methodology allows non-invasive longitudinal monitoring of endogenous and exogenous light absorbers as well as ultrasound imaging in anaesthetized mice.
- In addition to the above in vivo imaging methodologies, mesoscopic fixed samples can be imaged in 3D for absorbance and emission with a bespoke Optical Projection Tomography (OPT) instrumentation.
Assessment of metabolism is carried out both in vitro and in vivo. There is a need to extrapolate observations obtained at a cellular level to the whole animal and vice versa. Biological phenomena have to be followed at different levels of complexity in order to appreciate fully their values and implications.
Metabolism and animal physiology are investigated with the following techniques:
- CLAMS (Columbus Instruments’ Comprehensive Lab Animal Monitoring System): The Clams is an integrated indirect calorimetry system for metabolic studies of small animals. It allows accurate measurement of energy expenditure and respiratory exchange ratio in order to deduce a metabolic rate for the animal under study.
- Seahorse bioscience XF24 and XFe96 analysers: These instruments simultaneously measure mitochondrial respiration and glycolysis in cultured cells.
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