Abstract 3564: Enalapril Increases Relative Myocardial Glucose Uptake Early Post-Ischemic Injury
Maintenance of anaerobic glycolysis immediately following acute myocardial ischemia is necessary for cell viability. We hypothesized that enalapril, a known cardioprotective agent, preserves glucose utilization in the infarct and border zones at 3 hours post ischemia-reperfusion (I/R) injury in a rat model.
Methods: PET imaging was performed 3 hours after I/R injury in rats pre-treated for 7 days with vehicle (V, n=9) or enalapril at 30 mg/kg po (E, n=9) using a microPET scanner and 13N-ammonia (13NH3 ) for perfusion and 18F-fluoredeoxyglucose (18FDG) for glucose uptake measurements. Infarct size was calculated at necropsy using TTC as a percent of risk region (% RR). Kinetic SUV analysis was used to compare regional PET activity in the Remote (Rem), Border Zone (BZ), and Defect (Inf) territories. Infarct size was similar between groups (V, % RR= 25.3 vs. E, % RR= 24.0, p=NS). The relative glucose uptake to perfusion was estimated by the ratio of 18FDG to 13NH3 by Group and Region. While E increased this ratio in the Rem zone, the ratio was markedly increased in the ischemic territories: the BZ and Inf zones (graph). Compared to control rats, E dramatically increased the glucose uptake relative to perfusion in the infarct and border zones early after infarction. These data suggest that enhancing glucose utilization in early post-ischemic myocardium may contribute to enalapril’s cardioprotective properties.