Extracellular magnesium and calcium reduce myotonia in isolated ClC‐1 chloride channel‐inhibited human muscle

@article{Skov2015ExtracellularMA,
  title={Extracellular magnesium and calcium reduce myotonia in isolated ClC‐1 chloride channel‐inhibited human muscle},
  author={Martin Skov and Frank Vincenzo Paoli and Jesper Lausten and Ole Baekgaard Nielsen and Thomas H. Pedersen},
  journal={Muscle \& Nerve},
  year={2015},
  volume={51}
}
Introduction: Experimental myotonia induced in rat muscle by ClC‐1 chloride channel‐inhibited has been shown to be related inversely to extracellular concentrations of Mg2+ and Ca2+ ([Mg2+]o and [Ca2+]o) within physiological ranges. Because this implicates a role for [Mg2+]o and [Ca2+]o in the variability of symptoms among myotonia congenita patients, we searched for similar effects of [Mg2+]o and [Ca2+]o on myotonia in human muscle. Methods: Bundles of muscle fibers were isolated from… 
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The presence of myotonia and paramyotonia on clinical examination and of myotonic discharges during electrodiagnostic (EDX) studies are important for the diagnosis of certain neuromuscular
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