Nav1.7 In Vitro PX Assay: HEK 293 cells stably transfected with human Nav1.7 were recorded in whole cell voltage clamp mode with the PatchXpress automated electrophysiology system (Molecular Devices, LLC, Sunnyvale, Calif.). Compound effects were measured on a partially inactivated state of the sodium channel. Cells were clamped to a holding potential yielding 20 to 50% inactivation. To elicit sodium current, channels were activated by pulsing to -10 mV for 20 msec. This voltage protocol was repeated at a rate of 0.1 Hz throughout the experiment. A single concentration of test compound was applied to cells for a duration of 3 minutes.
Nav1.5 In Vitro PX Assay: 293 cells stably transfected with Nav 1.5 were recorded in whole cell voltage clamp mode with the PatchXpress automated electrophysiology system according the manufacturer's specifications (Molecular Devices, LLC, Sunnyvale, Calif.). Cells were held at a holding potential of -50 mV to inactivate sodium channels. To elicit sodium currents the voltage was changed -120 mV to recover a portion of the channels, followed by delivery of test pulses of 20 msec duration to 0 mV, at 0.1 Hz. A single concentration of test compound was applied to cells for a duration of 5 minutes.
Selectivity index, ratio of IC50 for inhibition of human Nav1.1 expressed in HEK293 cells by electrophysiology assay to IC50 for inhibition of human Nav1.7 expressed in HEK293 cells by electrophysiology assay
Selectivity index, ratio of IC50 for inhibition of human Nav1.2 expressed in HEK293 cells by electrophysiology assay to IC50 for inhibition of human Nav1.7 expressed in HEK293 cells by electrophysiology assay
Selectivity index, ratio of IC50 for inhibition of human Nav1.3 expressed in HEK293 cells by electrophysiology assay to IC50 for inhibition of human Nav1.7 expressed in HEK293 cells by electrophysiology assay
Selectivity index, ratio of IC50 for inhibition of human Nav1.4 expressed in HEK293 cells by electrophysiology assay to IC50 for inhibition of human Nav1.7 expressed in HEK293 cells by electrophysiology assay
Selectivity index, ratio of IC50 for inhibition of human Nav1.5 expressed in HEK293 cells by electrophysiology assay to IC50 for inhibition of human Nav1.7 expressed in HEK293 cells by electrophysiology assay
Selectivity index, ratio of IC50 for inhibition of human Nav1.6 expressed in HEK293 cells by electrophysiology assay to IC50 for inhibition of human Nav1.7 expressed in HEK293 cells by electrophysiology assay
Ratio of unbound plasma concentration in mouse model of histamine-induced pain to IC50 for inhibition of mouse Nav1.7 expressed in HEK293 cells by electrophysiology assay
Ratio of unbound plasma concentration in mouse model of UVB-induced pain to IC50 for inhibition of mouse Nav1.7 expressed in HEK293 cells by electrophysiology assay