Figure 3.

Tau phosphorylation at Ser262 and Ser404 residues is not altered by NMDA. Phosphorylation and protein levels were estimated by Western blotting of cell extracts (40 μg proteins) obtained from hippocampal slices treated with 10 μM NMDA for 1 hour. Phosphorylated Tau levels, expressed relative to total Tau (i.e., Tau-5) levels, were measured with antibodies raised against Tau phosphorylated at Ser199-202, Ser262, and Ser404. The data are expressed as percentages of control values and are means ± S.E.M. of 3 measurements per cell extract obtained from 6 different rats. Since these experiments were performed independently, we determined statistical significance by unpaired t-test. **P < 0.01, NMDA-treated versus control.