Fig. 2

Pathological comparisons of the presubiculum and entorhinal cortex in Alzheimer’s disease. The image demonstrates the anatomy of the hippocampus and illustrates the difference in Aβ deposition between the presubiculum (green outline) and entorhinal cortex (blue outline). Fluorescent Aβ immunohistochemistry shows that the Aβ peptide is deposited in a diffuse manner in the presubiculum (b, white arrow) whereas defined Aβ plaques are shown in the entorhinal cortex (e). Thioflavin S staining highlights the Aβ plaques in the entorhinal cortex (f), whereas the presubiculum is negative for the Thioflavin S stain demonstrating the Aβ in the presubiculum contains pre-amyloid deposits (c). Tau immunohistochemistry shows a difference between the presubiculum (h) and entorhinal cortex (l) in the density of neuropil threads and neurofibrillary tangles. The microglial marker, Iba1, shows the total number of microglia being equal between the two regions (I and m), whereas CD68 and CR3–43 highlight the increase in the number of activated microglia in the entorhinal cortex (n and o) compared to the presubiculum (j and k). Bar in ‘a’ represents 1000 μm in a; 100 μm in b, c, e, and f; 50 μm in d, g and h-o