FIGURE 5.

No significant correlation between mossy fiber sprouting and seizure frequency in epileptic pilocarpine-treated mice. Timm staining of the dentate gyrus from a control (a1) and epileptic mouse (a2). Sections are 50% of the distance from the septal pole to the temporal pole of the hippocampus. g = granule cell layer; h = hilus; m = molecular layer. Mossy fiber sprouting is evident as black Timm staining in the granule cell layer and inner molecular layer in the epileptic mouse (arrows). (b) High correlation (slope = 1.049, R = 0.961, p <0.001, Spearman rank order correlation) between the percent area of the granule cell layer plus molecular layer with black Timm staining measured two ways: (1) as the average of three sections (17, 50, and 84% of the distance from the septal pole to the temporal pole) and (2) as the average of the entire 1-in-12 series of sections. Data from Buckmaster and Lew (2011), Lew and Buckmaster (2011), and Heng et al. (2013). (c) Septotemporal distribution of percent Timm-positive area. Values represent mean ± SEM. (d) Larger percent Timm-positive area in epileptic pilocarpine-treated mice (n = 114) compared to controls (n = 10, p ≤ 0.001, Mann–Whitney rank sum test). (e) Significant negative correlation between percent Timm-positive area and number of large (>12 μm soma diameter) hilar GluR2-positive neurons per dentate gyrus (R = 0.515, p <0.001, ANOVA). (f) No significant correlation between percent Timm-positive area and seizure frequency (R = 0.178, p = 0.058, ANOVA)