Figure 2.

Reconstruction of dentate granule cell somatodendritic morphology after filling the cell with biocytin during whole-cell patch clamp recording in hippocampal slices. After visualization of biocytin with avidin/horseradish peroxidase/diaminobenzidine, cells were reconstructed from serial sections with use of Neurolucida. Granule cells shown are representative of those cells having a hilar basal dendrite. HEGCs shown (A–C) were chosen to illustrate differences in the relative sizes of the apical and basal dendritic trees: predominantly apical (A), mainly apical (B), and apical and basal about equal (C). The apical dendrite of HEGCs could reach the outer edge of the dentate molecular layer (A,B) or be confined to the dentate hilus (C; the dendrite pointed to the left was considered the apical dendrite). Note the relatively sparse branching of HEGC apical dendrites compared to those of GE-SEs (D) and CGCs (E) and the relatively exuberant branching of the distal apical dendrite(s) of GC-SEs compared to that of CGCs. A photomicrograph of the HEGC in panel C is included for comparison with the reconstruction. CGC, normotopic granule cell from control rat; g, granule cell body layer; GC-SE, normotopic granule cell from rat that had experienced status epilepticus; h, hilus of the dentate gyrus; HEGC, hilar ectopic granule cell from rat that had experienced status epilepticus; m, molecular layer of the dentate gyrus; p, pyramidal cell body layer of area CA3c.