Figure 3.

The density of calretinin-immunoreactive cells has been examined in control samples with short (2–4 h) and long (8–10 h) post-mortem delay, and in non-sclerotic and sclerotic epileptic samples. The dentate gyrus (A and B), CA3 (C), CA1 regions (D and E) and the density of the horizontal presumable Cajal–Retzius cells (F) have been analysed. Significantly fewer calretinin-positive cells are present in every subregion in control samples with long post-mortem delay compared to controls with short post-mortem delay (A–E). In the non-sclerotic samples, CA3 region (C) and hilus (B) show a significant reduction in the immunolabelled cell number. In other regions, the density of calretinin-positive cells is similar to controls. In sclerotic cases, the density of calretinin-immunoreactive cells is reduced significantly compared to the control samples with short post-mortem delays except the CA1 region (A–C). The volume of the CA1 region is reduced considerably in the sclerotic hippocampus which may explain why there is no difference in the number of cells per area in this region (D). Therefore, the cell number per unit length of the CA1 region (mm) is also calculated and compared between the samples, this way the decrease is significant also in this subfield (E). The number of horizontal cells in the outer molecular layer of the dentate gyrus (presumable Cajal–Retzius cells) is significantly decreased in all epileptic cases and in control samples with long post-mortem delay (F). Stars label significant changes, P < 0.05.