Fig. 8. In situ hybridization ofHu mRNAs in adult mouse brain and spinal cord. Horizontal sections (11 μm) of adult mouse brain and spinal cord were hybridized with 33P-labeled antisense probes specific formHuB (A, D, G, J, M, P),mHuC (B, E, H, K, N, Q), andmHuD (C, F, I, L, O, R) cRNA probes. Hippocampal formation (Hf), olfactory bulb (Ob), cerebral cortex (Ctx), habenula (Hb), spinal cord (Sc), and cerebellum (Cb) are shown. Note that the hybridization signal of mHuB is intense in hippocampal pyramidal cells CA2, CA3, and CA4, mitral cell layer (mt), accessory olfactory bulb (ao), and dorsal root ganglia, but the signal is absent in the cerebellum except for some scattered cells in the granule cell layer (gr). The mRNA of mHuC is widely expressed in the adult nervous system, including hippocampal dentate gyrus (dg), pyramidal cells, glomerular (gl), mitral and granule cell layer (gr) of olfactory bulb, cortex, corpus striatum (st), medial habenula (mh), gray (gm) and white matter (wm) of spinal cord, dorsal root ganglia (drg), and Purkinje cells (p). mHuD expression is prominent in the entorhinal cortex (er), medial habenula, and dorsal root ganglia, but it is absent in dentate gyrus, corpus striatum, and Purkinje cells. No reactivity was observed with sense riboprobes (data not shown). v, Third ventricle;mol, molecular layer. Scale bars: 400 μm inA–C; 300 μm inD–F; 200 μm in G–I; 300 μm inJ–L; 400 μm in M–O; 100 μm inP–R.