FIGURE 2.

Formalin-induced cerebral metabolic activation. (A) Representative microPET images of brains from rats injected with PBS (left column) or with 5% Formalin (right column) into the right hind paw. Images are presented in different planes, as indicated. Warmer colors indicate higher uptake of ¹⁸F-FDG, hence higher metabolic activity. Small and large white circles depict regions that contains thalamus and somatosensory cortex, respectively. (B) averaged ¹⁸F-FDG uptake of the whole brain in rats that received PBS (white bar, N = 4) or 5% Formalin (black bar, N = 6) into the right hind paw. Bars represent mean+S.E.M. of the S.U.V. values (*p = 0.05, t-student test).