Voltage-gated sodium channels (VGSCs) play an important role in action potential generation and propagation and mediate the rapid influx of sodium ions that underlies the rising phase of the action potential in sensory nociceptive neurons (Blair and Bean, 2002). The Na+ channels, Nav1.3 and Nav1.7, together with Nav1.8 and Nav1.9, have been highlighted as significant molecular targets for the design of low MW blockers for the treatment of chronic pain. The Nav1.8 channel is highly expressed by small primary sensory neuronsand is closely related to the occurrence and development of various types of pain, such as inflammatory pain, neuropathic pain, and inflammatory pain. With Vx-548 reaching its effective endpoint in Phase II clinical practice, the Nav1.8 target has become a popular target for non addictive analgesics. The EPhys team in ICE has validated patch clamp method for human- and rat-derived Nav1.8 cell lines and action potentials (AP) of dorsal root ganglion neurons for drug screening.