Differential uptake of FDQ and DG during post-ischaemic reperfusion in theisolated, perfused rat heart

Fluorine-18 2-fluoro-2-deoxyglucose (FDG) and 2-deoxyglucose (DG) are widel y used as tracers of glucose uptake in the myocardium. Although there is ag reement that the two analogues behave similarly to glucose under control co nditions, there is growing evidence that some interventions (e.g. insulin s timulation or ischaemia/reperfusion) cause differential changes in their be haviour. The addition of a two-surface coil nuclear magnetic resonance (NMR ) probe and a dual-perfusion cannula to our recently developed PET and NMR dual-acquisition (PANDA) system allows us to collect PET (FDG) images and p hosphorus-31 NMR (2-deoxyglucose-6-phosphate) spectra simultaneously from e ach independently perfused coronary bed of the heart. We have used this tec hnique to study the effect of regional ischaemia/reperfusion on FDG and DG uptake in the isolated, perfused rat heart. During control perfusion, FDG u ptake was almost identical in both coronary beds. When one coronary bed was made ischaemic, FDG uptake ceased on that side but continued on the contro l side. Reperfusion failed to restore FDG uptake. In contrast, NMR spectra showed that, during reperfusion, the uptake and phosphorylation of DC did n ot differ between the two coronary beds. The results thus demonstrate that regional myocardial ischaemia/reperfusion has different effects on the upta ke of FDG and DG in the isolated, perfused rat heart.