Figure 4.
Soluble intracellular Aβ species are increased in 3-month-old APPSwe/PS1/CCR2−/− mice and are strongly correlated with spatial memory decline. Hemibrain extracts from soluble extracellular (a), intracellular (c), and membrane-associated proteins (e) of 3-month-old APPSwe/PS1 (A) and APPSwe/PS1/CCR2−/− (AC) mice were assessed by Western blot on a 10–20% Tris-Tricine denaturing polyacrylamide gel to separate Aβ species using anti-Aβ antibody 6E10. The intensity of each band was quantified by densitometric analysis and normalized per β-actin values. Ratios of Aβ species (Aβ/β-actin) are represented for extracellular (b), intracellular (d), and membrane-associated proteins (f). Please note the increase of soluble intracellular Aβ species in the brain of APPSwe/PS1/CCR2−/− mice. Positive significant correlations exist between spatial memory decline (water T-maze test) and soluble intracellular Aβ species (g–m) and, more importantly, for high-molecular mass products (g–j). Results are expressed as mean ± SEM; n = 4; Student's t test; *p < 0.05 and **p < 0.01, versus APPSwe/PS1. Correlation test was performed using the Spearman's correlation coefficient.