A Dual Tracer PET-MRI Protocol for the Quantitative Measure of Regional Brain Energy Substrates Uptake in the Rat |
| |
Authors: | Maggie Roy Scott Nugent Sébastien Tremblay Maxime Descoteaux Jean-Fran?ois Beaudoin Luc Tremblay Roger Lecomte Stephen C Cunnane |
| |
Institution: | 1.Research Center on Aging and Department of Physiology and Biophysics, Université de Sherbrooke;2.Sherbrooke Molecular Imaging Center, Étienne-Le Bel Clinical Research Center, Université de Sherbrooke;3.Department of Computer Science, Université de Sherbrooke;4.Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke |
| |
Abstract: | We present a method for comparing the uptake of the brain''s two key energy substrates: glucose and ketones (acetoacetate AcAc] in this case) in the rat. The developed method is a small-animal positron emission tomography (PET) protocol, in which 11C-AcAc and 18F-fluorodeoxyglucose (18F-FDG) are injected sequentially in each animal. This dual tracer PET acquisition is possible because of the short half-life of 11C (20.4 min). The rats also undergo a magnetic resonance imaging (MRI) acquisition seven days before the PET protocol. Prior to image analysis, PET and MRI images are coregistered to allow the measurement of regional cerebral uptake (cortex, hippocampus, striatum, and cerebellum). A quantitative measure of 11C-AcAc and 18F-FDG brain uptake (cerebral metabolic rate; μmol/100 g/min) is determined by kinetic modeling using the image-derived input function (IDIF) method. Our new dual tracer PET protocol is robust and flexible; the two tracers used can be replaced by different radiotracers to evaluate other processes in the brain. Moreover, our protocol is applicable to the study of brain fuel supply in multiple conditions such as normal aging and neurodegenerative pathologies such as Alzheimer''s and Parkinson''s diseases. |
| |
Keywords: | Neuroscience Issue 82 positron emission tomography (PET) 18F-fluorodeoxyglucose 11C-acetoacetate magnetic resonance imaging (MRI) kinetic modeling cerebral metabolic rate rat |
|
|