Nav1.4 slow‐inactivation: Is it a player in the warm‐up phenomenon of myotonic disorders?

  title={Nav1.4 slow‐inactivation: Is it a player in the warm‐up phenomenon of myotonic disorders?},
  author={Christoph Lossin},
  journal={Muscle \& Nerve},
Myotonia is a heritable disorder in which patients are unable to willfully relax their muscles. The physiological basis for myotonia lies in well‐established deficiencies of skeletal muscle chloride and sodium conductances. What is unclear is how normal muscle function can temporarily return with repeated movement, the so‐called “warm‐up” phenomenon. Electrophysiological analyses of the skeletal muscle voltage‐gated sodium channel Nav1.4 (gene name SCN4A), a key player in myotonia, have… 

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Myotonia congenita.