Neonatal flutamide treatment demasculinizes male 3xTg-AD adult brains and TP treatment defeminizes female brains in terms of Aβ pathology in a region-specific manner. Representative photomicrographs display Aβ immunoreactivity visualized in the subiculum (AD), CA1 of hippocampus (F–I), and frontal cortex (K-N). Scale bar = 100μm. Significant treatment differences were observed in quantification of Aβ immunohistochemistry load in the subiculum (E) [F (4,32) = 2.82, p = 0.05], the CA1 (J) [F (4,32) = 17.11, p < 0.0001] and the frontal cortex (O) [F (4,32) = 13.01, p < 0.0001]. Data are represented as mean values ± SEM. * p < 0.05 from opposite sex of same age group.