Figure 4. Time course of progression of AD-like pathology, as a percentage of either 0.5- or 3-mo-old OXYS rats in a group. (A) Rats exhibited a 47% loss of neurons in the CA1 region of the hippocampus between 0.5 and 12 mo of age. In addition, a 102% increase in the phospho-tau T181 level occurred between 3 and 23 mo of age. Total Aβ expression increased by 333% between 3 and 23 mo of age. (B) Aβ1–42 level is increased in the hippocampus of 12- and 23-mo-old but not 3-mo-old OXYS rats compared with disease-free (control) Wistar rats. Staining for Aβ1–42 (red). DAPI staining (blue) corresponds to cellular nuclei. Scale bars: 20 μm. (C) Photomicrographs demonstrate the Aβ deposits in the brain of OXYS rats detected by MOAB-2, clone 6C3. Scale bars: 50 μm. (D) Immunostaining for Tau (green) and phospho-tau T181 (red) in the cortex of 18-mo-old OXYS and Wistar rats. DAPI staining (blue) corresponds to cellular nuclei. The arrow shows colocalization of Tau and phospho-tau T181 in OXYS and Wistar rats, whereas the arrowhead shows phospho-tau T181 in OXYS rats. Scale bars: 20 μm. (E) The percentages of dead or damaged neurons in the CA1 region of the hippocampus in 15-mo-old OXYS rats are significantly greater compared with Wistar rats. Neurons were stained with cresyl violet. Adapted from reference 34 and Maksimova et al.