Figure 1

sc-tPA and tc-tPA differentially influence NMDAR signaling. (a) Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblotting of sc-tPA and tc-tPA prepared as described in the Materials and Methods section (100 ng per lane). (b) SDS-PAGE followed by immunoblotting of sc-tPA and tc-tPA. sc-tPA was added on cultured cortical neurons 13 DIV for 1 h either alone or in the presence of plasmin or aprotinin. (c) Calcium video imaging performed on primary cultures of cortical neurons (12 DIV). After control NMDA stimulations (2 × 25 μM, 30 s) used as baseline, neurons were incubated for 45 min in the presence of buffer (control, n=90 cells), sc-tPA or tc-tPA at 300 nM (sc-tPA, n=85 cells; tc-tPA, n=78 cells) prior to a second set of NMDA stimulations (2 × 25 μM, 30 s). Percentages of potentiation or inhibition after incubation are calculated for each cell. (d) Percentage of potentiation or inhibition after incubation for each group (mean±S.E.M.; *P<0.0001 Kruskal–Wallis test followed by Mann–Whitney test; ^#P<0.0001 Wilcoxon test comparison of preincubation and postincubation responses)