Reproducibility of Non-Invasive A1 Adenosine Receptor Quantification in the Rat Brain Using [18F]CPFPX and Positron Emission Tomography
- First Online:
- Cite this article as:
- Kroll, T., Elmenhorst, D., Weisshaupt, A. et al. Mol Imaging Biol (2014) 16: 699. doi:10.1007/s11307-014-0729-0
- 244 Downloads
The A1AR antagonist 8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine ([18F]CPFPX) has recently been shown to be a suitable radiotracer for quantitative in vivo imaging of the A1 adenosine receptor (A1AR) in rats. The present study evaluates the reproducibility of non-invasive longitudinal A1AR studies with [18F]CPFPX and a dedicated small animal positron emission tomography (PET) scanner.
Twelve male Sprague Dawley rats underwent four repeated dynamic PET scans with a bolus injection of [18F]CPFPX. A1AR availability was determined by different non-invasive approaches including simplified and multilinear reference tissue (olfactory bulb)-based models and graphical methods. The outcome parameter binding potential (BP) was evaluated in terms of variability and reproducibility.
Repeated estimations of [18F]CPFPX BPND gave reliable results with acceptable variability (mean 12 %) and reproducibility (intraclass correlation coefficients raging from 0.57 to 0.68) in cortical and subcortical regions of the rat brain. With regard to kinetic models, test-retest stability of the simplified reference-tissue model (SRTM) was superior to multilinear and graphical approaches.
Non-invasive quantification of A1AR density in the rat brain is reproducible and reliable with [18F]CPFPX PET and allows longitudinal designs of in vivo imaging studies in rodents.