Extracellular magnesium and calcium reduce myotonia in ClC-1 inhibited rat muscle

@article{Skov2013ExtracellularMA,
  title={Extracellular magnesium and calcium reduce myotonia in ClC-1 inhibited rat muscle},
  author={Martin Skov and Anders Riisager and James A. Fraser and Ole Baekgaard Nielsen and Thomas H. Pedersen},
  journal={Neuromuscular Disorders},
  year={2013},
  volume={23},
  pages={489-502}
}
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It is concluded that although changes of extracellular K+ influence both myotonia and the warmup, these changes are unlikely to explain warmup in myotonic patients.
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TLDR
A model myotonia was induced in the muscles in vitro, using either the chloride channel blocker anthracene-9-carboxylic acid or chloride-free Krebs solution, and a possible role for depolarization in preventing/reducing the myotonic response was discussed.
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It is concluded that recovery of excitability in K+-depressed muscles induced by muscle acidification is related to reduction in the inhibitory Cl− currents, possibly through inhibition of ClC-1 channels, and acidosis thereby reduces the Na+ current needed to generate and propagate an AP.
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