Co-cultures were prepared as described in Figure 9. (A–B) Examples of NG2 and MBP immunostaining in 14 days old co-cultures. Scale bar = (NG2) 60µm; (MBP) 40µm. Yellow arrows indicate oligodendrocyte-neurite contact points. (C) Percentage of NG2, PLP and MBP positive cells in 14 days old co-cultures. (D) The number of contact points with neurites was analyzed in control and siCav1.2 MBP+ cells. (E) Morphological complexity of control and siCav1.2 MBP+ cells was scored in 4 categories. Co-cultures were treated with high K+. Potassium was applied in three consecutive pulses (5min/each) distributed during the first 3h of the second, third and fourth day in vitro. After treatment, the morphological complexity (F), the percentage (G) and the number of contact points with neurites (H) of MBP+ cells was analyzed in each experimental condition. Values are expressed as mean ± SEM of four independent experiments. *p<0.05, **p<0.01, ***p<0.001 vs. respective controls.