Volumes and immunohistochemical images of hippocampus sub regions. A) Hippocampal volumes of segmented in vivo images. Whole hippocampus, dorsal CA1 and dorsal dentate gyrus regions (DG) were manually segmented. Ratios between nonTg and rTg4510 were shown as percentage (%). B) Iba-1 and CP13 antibody stainings of hippocampus (CA1) in 6 month-old rTg4510 and nonTg littermate. Activated microgila cells detected by Iba-1 were intensely stained in the rTg4510 hippocampus. CP13 staining in rTg4510 showed hyperphosphorylated tau accumulation in CA1 neurons. Scale bar=200 mm.