Histochemical staining of coronal mouse hippocampal sections (showing CA3 area) of aged female mice after KA treatment. Sections were prepared 7 days after administration of KA and stained by Nissl's method or with Fluoro-Jade B (FJB) staining. The sections were scored using a semi-quantitative grading system as described in the Methods. Histopathological scores are presented in the surviving IL-18 KO mice (n = 8) and WT mice (n = 7) (A). There was no difference in pathological changes after KA treatment between IL-18 KO and WT mice. Representative sections of both groups of mice are presented (B, saline-treated control WT mice; C, Nissl-stained KA-treated WT mice; D, Nissl-stained KA-treated IL-18 KO mice; E, FJB-stained KA-treated WT mice; F, FJB-stained KA-treated IL-18 KO mice). Bars = 100 μm.