Use-Dependent Block by Lidocaine but Not Amitriptyline Is More Pronounced in Tetrodotoxin (TTX)-Resistant Nav1.8 Than in TTX-Sensitive Na+ Channels

@article{Leffler2007UseDependentBB,
  title={Use-Dependent Block by Lidocaine but Not Amitriptyline Is More Pronounced in Tetrodotoxin (TTX)-Resistant Nav1.8 Than in TTX-Sensitive Na+ Channels},
  author={Andreas Leffler and Anne Reiprich and Durga P. Mohapatra and Carla Nau},
  journal={Journal of Pharmacology and Experimental Therapeutics},
  year={2007},
  volume={320},
  pages={354 - 364}
}
The excitability of sensory neurons depends on the expression of various voltage-gated Na+ channel isoforms. The tetrodotoxin-resistant (TTXr) Na+ channel Nav1.8 accounts for the electroresponsiveness of nociceptive neurons and contributes to inflammatory and neuropathic pain. Na+ channel blockers are clinically employed for chronic pain management, but side effects limit their use. There is conflicting information whether their potency to block tetrodotoxin-sensitive (TTXs) and TTXr Na… 

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