Figure 8.

Role of L-type VGCC, AMPAR, and phosphatases in control of glutamate-induced dephosphorylation at S1412 and S847. Western blots were performed on cortical cultured neurons (10–15 DIV), which were treated for 15 min with glutamate alone or glutamate plus nifedipine and CNQX as indicated. A, Lane 1, No glutamate; lane 2, 150 μm glutamate; lane 3, 150 μm glutamate plus 1 μm nifedipine; lane 4, 150 μm glutamate plus 10 μm CNQX; lane 5, 1 μm nifedipine; lane 6, 10 μm CNQX. B, C, Quantification of A. Significance is comparison with treatment with 150 μm glutamate (*p ≤ 0.001, **p ≤ 0.0003). D, Calcineurin and PP1 inhibitors block NMDAR-induced dephosphorylation of S847-PO₄ and S1412-PO₄. Lane 1, No drug control; lane 2, 30 μm glutamate; lane 3, 30 μm glutamate plus 2 μm ascomycin; lane 4, 30 μm glutamate plus 0.5 μm okadaic acid; lane 5, 150 μm glutamate; lane 6, 150 μm glutamate plus 2 μm ascomycin; lane 7, 150 μm glutamate plus 0.5 μm okadaic acid. E, F, Quantification of D. *p ≤ 0.002; **p ≤ 0.0001.