NaV1.8 - "Characterization of rNaV1.8 (ND7-23) on Nanion's Patchliner"
The NaV1.8 gene (originally named PN3 or SNS; gene symbol SCN10A) encodes a voltage-gated sodium (NaV) channel, selectively expressed in dorsal root ganglion (DRG) neurons. DRGs transmit peripheral stimuli to the central nervous system and are involved in nociception. Different NaV channels play a key role in modulation of DRG action potentials. In particular, the fast upstroke of the action potential is mediated by NaV channels. NaV channels are in part characterized by their TTX-sensitivity (TTX-resistant [TTXr], TTX-sensitive [TTXs]). NaV1.8 is a TTXr channel. Compared with other NaV channels, NaV1.8 has slow activation and inactivation kinetics and is opened at relatively high voltages. It is an interesting drug target for inflammatory and neuropathic pain, because modulation of NaV1.8 by inflammatory mediators seems to be a key mechanism of DRG nociceptor sensitization and activation. Interestingly, NaV1.8 has been reported to play an important role in the perception of cold pain. In this Application Note we present data recorded on the Patchliner characterizing ND7-23 cells (a rat DRG/mouse neuroblastoma hybrid) stably transfected with rat NaV1.8. All experiments were performed in the presence of 100 nM TTX to block the endogenous TTXs Na+ current present in these cells. The NaV1.8 activation and inactivation properties and tetracaine sensitivity recorded on the Patchliner were consistent with those reported in the literature.