C. Time course of the peak AMPAR-mediated synaptic response to Schaffer collateral stimulation before, during, and after the induction of LTD by LFS (300 pulses at 1 Hz), in control (uninfected) and GSK3α (blue) or GSK3β (orange) shRNA-expressing neurons. Error bars represent SEM. D. Quantification of average synaptic depression from the last 5 minutes of the time course shown in C. Error bars represent SEM. Statistical significance was calculated according to the Mann-Whitney U test. E. Cumulative frequency distribution of the ESPC values plotted in D. Statistical significance was calculated according to the Kolmogorov-Smirnov test. 