Fig. 3
NVC attenuates divalent-dependent increase in evoked APs. A Exemplar traces showing AP firing following incremental 1 s current injections of 10–40 pA from RMP. Blue represents control and red NVC. Dark tracers represent Ca1.1 and light Ca0.2. B Graphs showing average AP count in control (blue) and NVC (red), measurements in Ca1.1 (solid, filled circles) and Ca0.2 (faint, open circles) represented by separate lines. Error bars represent standard error. Mean AP counts in control Ca1.1 = 7.5 ± 1.8 and increase to 19.7 ± 2.4 in control Ca0.2 at 40 pA, whereas NVC AP counts at the same current injections ranged from 9.2 ± 2.1 at NVC Ca1.1 to 12.8 ± 2.9 at NVC Ca0.2. C Plot showing average cumulative elicited AP count in control (blue) and NVC (red) for each recording. Mean values for Ca1.1 represented by solid diamonds and Ca0.2 by open diamonds. Mean values for control Ca1.1 and Ca0.2 were 16.5 ± 5.1 and 58.6 ± 8.0, whereas NVC Ca1.1 and Ca0.2 were 30.2 ± 7.6 and 43.1 ± 9.0, respectively. Individual values represented by open circles connected by a line showing change in cumulative AP count following switch from Ca1.1 to Ca0.2. Error bars represent standard error. Comparison by two-way RM ANOVA shows no interaction between divalent concentration and NVC treatment (F (1,48) = 3.616, P = 0.06) or independent effect of NVC (P = 0.91) but decreasing divalents had an effect (P = 0.0008). Post hoc analysis with Sidak multiple comparisons shows different effects in control and NVC, with increase in average cumulative AP count in control (P = 0.0005) but no effect of NVC (P = 0.436). N = 26 and 24 for control and NVC groups