Fig. 4.
Representative in vitro autoradiographic images of the binding pattern of [18F]FLUDA (0.93 nM) in horizontal mouse brain slices. The highest accumulation of activity in the striatum (a, red). The binding is completely blocked by co-administration of 10 μM of the A2A receptor antagonist ZM241385 (b). For annotation of the brain regions, the slices were Nissl-stained after autoradiography (c). St striatum, Cb cerebellum, and Cx cortex, Th thalamus. Representative competition curve (d). KD and Bmax calculated from the homologous completion of [18F]FLUDA with FLUDA (Cheng-Prusoff equation KD = IC50− [[18F]FLUDA] and Bmax = top – bottom ∙ (KD + [[18F]FLUDA])/[[18F]FLUDA] [20].