ZENON mRNA colocalizes with MAP2 mRNA in adult brain. (Upper panels) Serial adult rat sections (250 μm) were hybridized with Dig-ZENON and Dig-MAP2 riboprobes, which were detected by NBT-BCIP. Bars, 1 mm. The letters indicate the regions from which doubly stained sections A to H were taken. (Lower panels) Adult rat brain sections (14 μm) were hybridized with Dig-ZENON and Fluo-MAP2 riboprobes, which were consecutively detected by incubation with NBT-BCIP (blue) and INT-BCIP (red) substrates. For each brain region examined, a double-labeling experiment and in situ hybridization with the Dig-ZENON riboprobe only performed on adjacent sections are shown in parallel. Bars, 50 μm. Insets show higher magnifications (bars, 10 μm) of the doubly labeled cells. A, olfactory bulb; B, pyriform cortex; C, cerebral cortex; D, striatum; E, hippocampus; F, thalamus; G, pons; H, cerebellum.