Fig. 1.

Low-power photomicrograph of mouse dentate gyrus from a section immunolabeled with anti-GFAP antibody to reveal the laminar distribution of astrocytes and to define the layers and limits of the dentate gyrus. Note the boundaries of the granular layer (Gr, pink) are demarcated by adjacent molecular (Mol, blue) and polymorphic (Pol, green) layers. Reduced GFAP immunostaining in the CA3 pyramidal layer (CA3Py) clearly delineates the boundary between the polymorphic layer and the pyramidal layer. The grid (straight green lines parallel to the x- and y-axes) establishes the intervals between the orange square boxes and illustrates the random and systematic sampling approach. The number of boxes in each section is proportional to the area covered by the dentate gyrus. A single astrocyte located inside every box was selected for three-dimensional reconstruction. Scale bar 250 μm