Figure 7: Knockdown of Cdk5 in the contralateral PL reverts the deactivation of PL excitatory neurons.

(a) Expression of Cdk5 shRNA lentiviruses in the PL (Bregma 2.30 mm). (b) Cdk5 protein level after infection of lentiviruses that express Cdk5 shRNA (**P<0.05, paired t-test). (c) p-Cdk5 protein level after infection of lentiviruses that express Cdk5 shRNA (*P<0.05, paired t-test). (d) Number of spikes induced by injected currents in the contralateral PL excitatory neurons from the rats injected with lentiviruses that express non-silence shRNA or Cdk5 shRNA 1 day after CFA (n=22, 19 neurons, *P<0.05, **P<0.01, ***P<0.001, two-way ANOVA with Bonferroni post tests). (e) Examples of AP responses to positive current steps recorded from pyramidal neurons from the non-silence shRNA and Cdk5 shRNA rats 1 day after CFA. (f) The current required to drive APs at a frequency of 12.5 Hz was smaller in the Cdk5 shRNA rats (215.8±19.92 pA, n=19 neurons) compared with the non-silence shRNA rats (287.3±17.13 pA, n=22 neurons; **P<0.01, two-tailed t-test). (g) Phase plots of APs from the non-silence shRNA and Cdk5 shRNA rats 1 day after CFA evoked by brief current injections. Note the different initial point of the firing threshold. (h) Plot diagram summary of the AP thresholds from the non-silence shRNA rats (−25.09±1.590 mV, n=18 neurons) and Cdk5 shRNA rats (−30.49±1.692 mV, n=18 neurons, *P<0.05, two-tailed t-test) 1 day after CFA. (i) Representative sEPSC recording traces from the rats injected with lentiviruses that express non-silence shRNA or Cdk5 shRNA. Scale bars, 10 pA and 500 ms. (j, k) Cumulative probabilities (Frequency distribution, ***P<0.001; Amplitude distribution, **P<0.01; Kolmogorov–Smirnov two sample test) and average sEPSC frequencies and amplitudes from the non-silence shRNA group (frequency: 0.8224±0.7596 Hz, amplitude: 11.32±0.4476, pA, n=16 neurons) and the Cdk5 shRNA group (frequency: 0.7664±0.1192 Hz, amplitude: 12.16±0.6138, pA, n=16 neurons, two-tailed t-test). The data are presented as mean±s.e.m.