Figure 6.
Reduced degree of SK-dependent SFA of Cav1.3−/− MCCs is reflected in an increased degree of Na+ channel inactivation and progressive changes of the AP waveform. a, Overlap of APs, together with their respective phase plane plots (dV/dt vs V) retrieved from a spike train triggered by 15 pA current injection for WT MCCs (top, black), Cav1.3−/− MCCs (middle, blue), and WT MCCs perfused with apamin (bottom, red). b, Evolution of the peak amplitude with time for WT (black squares), Cav1.3−/− (blue dots), and WT MCCs perfused with apamin (red triangles) (***p < 0.001). c, Same as for b, but taking into consideration dV/dtmax (**p < 0.01; ***p < 0.001). d, Comparison of Vthresh in control (ctrl; black bars) and during apamin application (apa; red bars) between the first AP and the last AP of the spike train for WT MCCs (left) and Cav1.3−/− MCCs (right) (*p < 0.05). Degree of significance was determined by a one-way ANOVA followed by a Bonferroni post hoc analysis.