- Terry L Sharp: Division of Radiological Sciences, The Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8225, St. Louis, MO 63110, USA.
INTRODUCTION: An increasing number and variety of studies on rodent models are being conducted using small-animal positron emission tomography scanners. We aimed to determine if animal handling techniques could be developed to perform routine animal imaging in a timely and efficient manner and with minimal effect on animal physiology. These techniques need to be reproducible in the same animal while maintaining hemodynamic and physiological stability.
METHODS: The necessary techniques include (a) the use of inhalant anesthesia, (b) arterial and venous cannulation for multiple tracer administrations and blood sampling, (c) development of small-volume analytic columns and techniques and (d) measurement of the physiological environment during the imaging session.
RESULTS: We provide an example of a cardiac imaging study using four radiotracers (15O-water, 1-[11C]-acetate, 1-[11C]-palmitate and 1-[11C]-glucose) injected into normal rats. Plasma substrates, CO2 production and total metabolites were measured. The animals remained anesthetized over the entire imaging session, and their physiological state was maintained.
CONCLUSION: The intrastudy stability of the physiological measurements and substrate levels and interstudy reproducibility of the measurements are reported.