Schematic illustration of the stereological methods for quantification of Prox1/Dcx-positive cells in hilus. The upper panel represents the tracing procedure for the contour of the hilar region. Some 50 μm diameter circles were placed on the interior of the granule cell layer to exclude the SGZ. The boundaries of hilus was traced along the edge of the circles in hilus, from the vertex of the granule cell layer to a straight line drawn between the two lateral tips of the granule cell layer. The lower panel demonstrates a counting frame of 50×50 μm distributed in a randomly oriented 150×150 μm XY grid. Only the grids within the traced contour were included. GCL: granule cell layer; H: hilus.