Figure 6.

Rheb^CA-induced seizures are associated with increased microglial activation. A, Images of IBA1 staining in ipsilateral and contralateral cortices from control, low Rheb^CA, and intermediate Rheb^CA mice. Top, IBA1 staining (red) and GFP⁺ cells (green). Bottom, Inverted grayscale images of the same IBA1 staining as in the top panels. Scale bar, 100 μm. Ipsi, Ipsilateral; Contra, contralateral. B, Quantification of IBA1⁺ cell density in ipsilateral cortices. Open circles within the intermediate Rheb^CA condition indicate animals with ≤1 seizure. p = 0.0091 by one-way ANOVA. Tukey's post hoc test: **p < 0.001. C, Scatterplot of mean number of seizures per day versus IBA1⁺ cell density. r = 0.5502, p = 0.0441 by Spearman's rank–order correlation. D, Quantification of IBA1⁺ cell density in ipsilateral and contralateral cortices. p = 0.0414 by two-way repeated-measures ANOVA. Bonferroni post hoc test: *p < 0.01, **p < 0.01, ***p < 0.001, ****p < 0.0001. E, Quantification of IBA1⁺ cell size in ipsilateral cortices. Open circles within the intermediate Rheb^CA condition indicate animals with ≤1 seizure. p = 0.0043 by one-way ANOVA. Tukey's post hoc test: *p < 0.05, **p < 0.01. F, Representative images of IBA1-labeled microglia morphology in tissue from control, low Rheb^CA, and intermediate Rheb^CA mice. Top, IBA1 staining (red) and DAPI-stained nuclei (blue). Bottom, Inverted grayscale images of the same IBA1 staining as in the top panels. The most apparent microglia morphology observed in control and low Rheb^CA tissue was ramified, whereas microglia in intermediate Rheb^CA tissue displayed a variety of morphologies, including ramified (indicated by white arrow), hypertrophic, bushy, and rod. Error bars indicate ± SEM. Con, Control; Int, intermediate.