Fig. 9.

Increased phosphorylation of tau occurs with age in Tg2576/PS1^P264L cortex. Whereas concentrations of total tau are relatively constant with increasing amyloid burden (bottom blot), phosphorylated tau at thr231 increases in intensity (top blot), as does the higher molecular weight species stained with the antibody to total tau in Tg2576/PS1^P264L mice (bottom,arrow). This higher molecular weight tau species comigrates with phosphorylated tau stained with both phospho-tau antibodies used in this study. The phosphorylated tau epitope ser202 increases as well in 12-month-old Tg2576/PS1^P264Lcortex, as seen in Figure 2. WT 12, Wild-type mice at 12 months of age.