Fig. 2

D1r downregulation in adolescence is associated with complement C3 and microglial lysosomal degradation in the male, but not the female, NAc. To assess microglial phagocytic activity and whether D1r, C3, or C3-D1r were localized in microglial CD68+ lysosomes, immunohistochemistry for CD68, D1r, and C3 was performed. a Representative 2D triple-label immunohistochemistry (scale bar 20 µm), with enlarged 3D representation (scale bar 2 µm) of the selected area demonstrating (left-right) D1r, C3, and C3-D1r within CD68+ lysosomes. Closed arrow head indicates a lysosome where D1r and C3 colocalize (C3-D1r). Males: c CD68 levels are high from P30 to 38 (Table 2A). b D1r content in CD68+ lysosomes is highest at P30 (Table 2B), d C3 content in lysosomes does not change over development (Table 2C), and e C3-D1r content in lysosomes is transiently elevated at P30 (Table 2D). Females: f CD68 levels are transiently elevated at P30 (Table 2E). g D1r content in CD68+ lysosomes is high at both P30 and P54 (Table 2F), h C3 content in lysosomes is highest at P20 and P54 (Table 2G), and i C3-D1r content in lysosomes does not change over development (Table 2H). For all experiments, n = 4 animals/sex/group. Data were analyzed with one-way ANOVAs and Holm-Sidak’s post-hoc comparisons. Histograms portray the mean ± SEM with individual data points overlaid. Significant post-hoc Holm-Sidak t-tests (p < 0.05) comparisons are delineated with an asterisk. All statistics are in Table 2