A–C, Low-power photomicrographs showing the patterns of reelin expression in the olfactory bulb at P0, P5, and P21. D, Double-labeled (radioactive and nonradioactive ISH) section illustrating the lack of colocalization between reelin mRNA (silver grains, mitral cells) and GAD67 expression (black, granule cells) in the olfactory bulb at E18.E, Photomicrograph showing the bilaminar distribution ofreelin-expressing cells in the olfactory bulb at P21.F, Dark-field image of a double-labeled preparation (radioactive and nonradioactive ISH) of a field similar to that inE, showing the lack of colocalization betweenreelin mRNA (white labeling, silver grains) and GAD67 mRNA (black) in the olfactory bulb (Figure legend continues)at P21. G, H, Distribution ofreelin-expressing cells in the basal forebrain at P0.Acb, Nucleus acumbens; Amg, amygdala;AOB, accessory olfactory bulb; CPu, caudate-putamen; fi, lamina fibrorum; gl, lamina glomerulosa; GP, globus pallidus;gre, lamina granularis externa; gri, lamina granularis interna; HDB, horizontal limb of the diagonal band; lmi, lamina medularis interna;lo, lateral olfactory tract; LS, lateral septum; mfb, medial forebrain bundle;mi, lamina cellularun mitralium;MS, medial septum; obn, olfactory bulb neuroepithelium; Pir, cortex piriformis;ple, lamina plexiformis externa; pli, lamina plexiformis interna; PO, preoptic area;Tu, olfactory tubercle; VDB, vertical limb of the diagonal band. Scale bars: A–C, G, H, 500 μm; D–F, 100 μm.