Abstract 13236: The Use of 18f-fdg to Detect Changes in Atherosclerotic Lesions in Atherogenic Apoe -/- Mice
Background: F-18-fluorodeoxyglugose (F18-FDG) is a glucose analogue taken up by active macrophages in the atherosclerotic plaque.Using 18F-FDG as a marker of monocyte metabolism and plaque inflammation, we aim to determine whether F18-FDG PET could be used to monitor atherogenesis in mice using micro-positron emission tomography (uPET) as well as computed tomography (CT) in order to examine disease progression.
Methods and Results: Ten male C57BL/6 ApoE-/- mice were used. At 8 weeks of age, 5 mice were put on a high-fat high-cholesterol diet (HFD) for 12 weeks to induce atherosclerotic lesions and 5 mice were put on a regular chow diet for 12 weeks as controls. Following the HFD period, mice were injected (i.v) with 1mCi 18F-FDG while under 1.5% isoflourane. Mice were scanned 1hr post injection using a uPET scanner for 30mins followed by a 9min uCT scan. Aorta were dissected and imaged ex vivo by uPET for 15min followed by autoradiography imaging. Different organs including heart, ascending aorta, branches and descending aorta were counted with a gamma counter for biodistribution. Autoradiography images show significant uptake in the aortic lesions corresponding to lesions seen on light microscopy with a correlation coefficient of 0.83. Biodistribution data shows a statistically significant increase in 18F-FDG uptake in the aorta of mice fed a HFD compared to the control group. Average of the % injected dose per gram of tissue (%ID/g) ± SDEV for aortic branch was 12.56 ± 6.48 vs. 2.6 ± 2.6 (p = 0.05) for HFD vs. chow fed mice; aortic arch uptake was 11.47 ± 3.38 for HFD vs. 3.56 ± 2.8 (p = 0.011) for chow fed mice. Whole body in vivo uPET scans of mice on HFD show significant increase in 18FDG uptake in the aorta (SUV± SDEV; 4.65 ± 0.5) vs. ( 1.8 ± 0.8) for control mice. Ex vivo aorta of mice on HFD had a higher SUV value ( 0.64 ± 0.3) vs. control mice ( 0.25 ± 0.09).
Conclusion: 18F-FDG can be used as non-invasive method to monitor plaque in an atherogenic mouse model.
- © 2011 by American Heart Association, Inc.