Figure 3. N-type and non-N-type current densities in sensory neurons of Cacna1b^b*b/b*b mice are indistinguishable from WT.

Average N-type (a–c) and non-N-type (d–f) calcium current voltage relationships in three sub-types (small, large, and T-rich) of acutely dissociated DRG neurons from wild-type (WT), Cacna1b^b*b/b*b (b*b), and Cacna1b^aa*/aa* (aa*) mice (a–f). Representative currents shown above current voltage plots evoked by test pulses to 0 mV from a holding potential of − 80 mV, recorded from each cell type, and each mouse line. Currents were elicited as described in Fig. 2 and plotted as pA/pF to normalize for cell size. N-type currents and non-N-type currents correspond to ω-conotoxin GVIA-sensitive and insensitive components of the whole cell current, respectively. N-type currents were isolated in each cell by subtracting non-N-type (insensitive to 2 μM ω-Ctx GVIA) from whole cell currents. N-type current densities in small (a) and large (b) neurons are significantly smaller in Cacna1b^aa*/aa* compared to WT mice. Individual current voltage plots were fit with one (a–e) and two (f) Boltzmann functions using average parameters calculated from fitting individual curves (Supplementary Table 2). Scale bars represent 500 pA and 5 ms. Data points are mean ±s.e.m. n values shown are number of cells but all data sets contain recordings from at least 9 mice.