Determination of mTOR activity by p70S6K and 4E-BP1 in brain tissue of young, adult and old C57BL/6J mice. Panel (A) shows the amount of p-p70S6K, while panel (B) demonstrates the basal amount of the protein in young, adult and old murine brain tissues from C57BL/6J male mice. The immunoblots are shown for four individual mice per age group. In panel (C) the ratio of p-p70S6K to basal p70S6K is given. Panels (D-F) show the analysis of 4E-BP1. Panel (D) demonstrates the amount of the p-4E-BP1, followed by panel (E), indicating the amount of the basal 4E-BP1 protein. The ratio of the p-4E-BP1 to 4E-BP1 is given in panel (F). All data were analyzed in relation to GAPDH and data are shown as percentages in relation to the young control. Statistical significant differences between young, adult and old murine brain samples were calculated, using one-way ANOVA, followed by Tukey's post hoc test and are indicated by *p<0.05 and **p<0.01, all compared to young control..