Fig. 4. An atlas of cell density using the three labeling methods.

Schematic, rostral-to-caudal, density-atlas sections demonstrate that astroglial density varies considerably in the adult CNS. Antero-posterior (AP) coordinates, in mm from Bregma, are indicated above the schematics. The colorimetric density gradient (top) represents increasing density (defined as the number of astroglia per mm² in 30 μm sections). Schematic representations of neuronally defined regions are based on Franklin and Paxinos (1997). Abbreviations: am, amygdala; cc, corpus callosum; cl, claustrum; ctx, cortex; dr; dorsal root, spinal cord; fi, fimbria; fmi, forceps minor, corpus callosum; fo, fornix; gc, granule cell layer, cerebellum; gl, glomerular cell layer, olfactory bulb; gm; grey matter, spinal cord; gp, globus pallidus; gr, granule cell layer, olfactory bulb; hpc, hippocampus; hyp, hypothalamus; ic, internal capsule; ls, lateral septal nucleus; mg, medial geniculate nucleus, thalamus; ml, molecular layer, cerebellum; mm, mammilary nucleus; na, nucleus accumbens; po, preoptic nucleus, hypothalamus; sc, superior colliculus; sn, substantia nigra; str, striatum; vp, ventral pallidum; wm, white matter, spinal cord; zi, zona incerta.