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Updated: Oct 19, 2026

Establishing a Mouse Model of a Pure Small Fiber Neuropathy with the Ultrapotent Agonist of Transient Receptor Potential Vanilloid Type 1
Published on: February 13, 2018
The tetrodotoxin-resistant sodium channel SNS has a specialized function in pain pathways
A N Akopian1, V Souslova, S England
1Molecular Nociception Group, Department of Biology, Medawar Building, University College, London WC1E 6BT, UK.
Abstract:
Many damage-sensing neurons express tetrodotoxin (TTX)-resistant voltage-gated sodium channels. Here we examined the role of the sensory-neuron-specific (SNS) TTX-resistant sodium channel alpha subunit in nociception and pain by constructing sns-null mutant mice. These mice expressed only TTX-sensitive sodium currents on step depolarizations from normal resting potentials, showing that all slow TTX-resistant currents are encoded by the sns gene. Null mutants were viable, fertile and apparently normal, although lowered thresholds of electrical activation of C-fibers and increased current densities of TTX-sensitive channels demonstrated compensatory upregulation of TTX-sensitive currents in sensory neurons. Behavioral studies demonstrated a pronounced analgesia to noxious mechanical stimuli, small deficits in noxious thermoreception and delayed development of inflammatory hyperalgesia. These data show that SNS is involved in pain pathways and suggest that blockade of SNS expression or function may produce analgesia without side effects.
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