The SCN is a region of low NeuN expression in the adult brain but SCN DCX is localized in NeuN+ neurons. A-C: Photomicrographs of one field within the ventral hypothalamus of the adult rat brain showing NeuN in neurons and the absence of NeuN within OC glia. Note the low expression of NeuN in the SCN, particularly in the dorsal region. The boundaries of the SCN are marked with dashed lines. Scale bar = 100 μm. D-F: Photomicrographs of neurons within one field of the ventral SCN showing the localization of DCX within NeuN-positive neurons. Note the low relative level of NeuN in the DCX-positive, and some other cells (single arrowheads) compared with the higher level in the majority of DCX-negative cells (examples indicated with double arrowheads in E). Scale bar = 20 μm. Abbreviations: 3V, third ventricle; OC, optic chiasm.