Figure 2. Brain glucose uptake decreases as a function of age .
Dynamic microPET scanning using 18F‐labelled fluorodeoxyglucose (FDG)‐PET as a tracer in Fischer 344 rats demonstrated a significant decline in glucose uptake and metabolism in 24‐month‐old rats as compared to 6‐month‐old rats. Calculation of selective uptake values (SUV), which measures the kinetics of glucose uptake, demonstrates that the SUV for the 24‐month rat is lower than the 6‐month rat (at end of scan, 2.72 as compared to 3.34).