Figure 7

Effect of ranolazine on the excitability of DRG neurons expressing WT, L858H or V1298F channels. Action potentials were recorded in current-clamp mode from DRG neurons transfected with WT (panel A), the IEM mutant L858H (panel B), or the PEPD mutant V1298F (panel C), channels as described in the Methods section. The number of action potentials elicited during current injections of 1-sec duration ranging from 50 pA to 1000 pA in 50 pA increments are counted both before and then again after exposure to 10 μM ranolazine. In this figure, cells whose response did not exceed 5 spikes were removed to compare just the high firing cells. The average number of action potentials elicited at each current injection level are plotted before (grey) and after 10 μM ranolazine (solid) exposure. In each panel the two datasets are shown to compare the response to ranolazine in cells expressing WT (panel A, n = 10), the IEM mutant L858H (panel B, n = 4), or the PEPD mutant V1298F (panel C, n = 5), channels.