FIGURE 13.

Densitometric analysis of age- and AD-related decrease in Shank3 IR in representative human brain subregions. (A–D) show the sampling of brain sections relative to the lateral view of the human brain, with the shapes of a frontal slice passing the prefrontal cortex (B), a frontal slice passing postcentral gyrus and mid-hippocampus (C) and a horizontal slice passing the mid-cerebellum (D), drawn schematically. The framed areas marked in purple represent the approximate locations of the “areas of interest” for the measurement of optic densities (o.d.) of Shank3 IR in the sections within the above thick brain slices. Panel (E) shows the original images extracted at 4 × magnification from gyral portions of the prefrontal neocortex, the hippocampal formation covering the middle segment of the dentate gyrus and cortex of the posterior cerebellar lobe, using the Motic-scanned whole region images. Panel (F) is corresponding pseudocolor screen prints of OptiQuant working interfaces, wherein measuring templates are illustrated. Thus, the o.d. (expressed as DLU/mm²) obtained from the gray matter regions (i.e., layers I–VI, ML, GCL) is defined as the total density of the IR, while the o.d. measured in the nearby white matter (WM) area is considered as the background (the cutoff level). The specific o.d. is calculated by subtracting the background from the total o.d. in the corresponding areas of interest. Panel (G) pots the means of specific o.d. of Shank3 IR obtained from the indicated neocortical areas (layers I–VI), the molecular layer (ML) of the dentate gyrus (DG), and the ML and GCL of the cerebellar cortex in individual brains in youth, adult, aged, and AD groups. Statistics (one-way ANOVA with Bonferroni’s post hoc test) are as indicated. Additional abbreviations are as defined in Figure 3. * indicating significant difference of the means of individual pairing groups according to Bonferroni’s multiple comparison post hoc test.