18F-FDG-uptake by PET/CT in a Transgenic Murine Model of Myocardial Infarction.

Aim: to investigate by molecular imaging the role of UCP3 protein in cardiac remodelling in a transgenic murine model of myocardial infarction. Methods: 20 control, and 15 wild type and 5 UCP3 knockout infartuated C57Bl/6J mice, 9-16 weeks aged, were analyzed with 18F-FDG PET/CT (eXplore VISTA GE, spatial resolution PET 1.4 mm FWHM, CT 200 ?m). Left ventricle mean uptake values (SUV, MBq/ml) have been measured with eXplore VISTA analysis tool in a representative axial slice; surface area and volume have been calculated in vivo with MunichHeart software from polar maps. Results: Left ventricle 18F-FDG mean uptake in healthy mice resulted 2.018±0.979 SUV/ 0.505±0.235 MBq/ml, whereas mean surface area and volume were 72.37 mm2 and 56.62 ?l respectively. 18F-FDG uptake in infartuated mice resulted 2.57±0.73 SUV/0.66±0.38 MBq/ml for wild type, 4.48±1.21 SUV/1.12±0.37 MBq/ml for UCP3 knockout mice (p 0.0031 and 0.002, Wilcoxon test, respectively). Mean values of surface area and volume in infartuated mice were 91.87 mm2 and 75 ?l, more than 20.5% (p 0.0034), and 17.7% (p 0.18, Wald test) of healthy mice, respectively, without significative changes over time ( p>0,05). Conclusions: UCP3 play a crucial role in mitochondrial energy metabolism and reactive oxygen species (ROS) generation. 18F-FDG PET in genetically engineered mice have emerged as important research tool to understand myocardial ischemic disease processes and to evaluate potential target of therapies.