Figure 6: Photomicrographs showing MC1 immunoreactivity within the hippocampal CA1 field ((a)–(c)), BLA ((d)–(f)) and subiculum ((g)–(l)) at 3-week, 2–4-, 8-9-, and 20-month-old 3xTg-AD mice. Dashed line in (d) and (f) outlines the area containing the BLA. Note the increase in MC1 neuronal immunostaining in hippocampal CA1 neurons ((b), higher magnification shown in insert), the neuropil in the BLA (e) at 2–4 month and the reduction in reactivity in these areas in 9-month-old mutant mice ((c), higher magnification shown in insert and (f)). Low-magnification images of the subiculum from male (g) and female (j) 20 months of old 3xTg-AD mice. Example of MC1-ir neurites was observed in the subiculum of a male mutant mouse ((h)). Both male ((i)) and female ((j), higher magnification of boxed area shown in (l)) mutant mice displayed dystrophic subicular MC1-ir neurons. Scale bars: ((a)–(f)); ((g), (J)) =100  m, insets = 35  m, ((h), (i), (k), (l)) = 20  m.