Elsevier

Neuroscience Letters

Volume 185, Issue 1, 6 February 1995, Pages 70-73
Neuroscience Letters

Expression of tetrodotoxin-resistant sodium channels in capsaicin-sensitive dorsal root ganglion neurons of adult rats

https://doi.org/10.1016/0304-3940(94)11227-AGet rights and content

Abstract

We have used conventional whole-cell electrophysiological recording techniques to measure the level of expression of tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) sodium currents in the capsaicin-sensitive and capsaicin-insensitive subpopulations of dorsal root ganglion neurons. We find that there are significantly higher levels of TTX-R expressed in the capsaicin-sensitive group but no difference in the levels of TTX-S. Since capsaicin is a selective stimulant of polymodal nociceptors, these data raise the possibility that TTX-R sodium channels may be an important determinant of nociceptor phenotype.

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