Impairment of slow inactivation as a common mechanism for periodic paralysis in DIIS4-S5

  title={Impairment of slow inactivation as a common mechanism for periodic paralysis in DIIS4-S5},
  author={Sa{\"i}d Bendahhou and Theodore R. Cummins and Roger W. Kula and Y.-H. Fu and Louis J. Pt{\'a}{\vc}ek},
Background Mutations in the human skeletal muscle sodium channels are associated with hyperKPP, hypoKPP, paramyotonia congenita, and potassium-aggravated myotonia. This article describes the clinical manifestations of a patient with hyperKPP carrying a mutation (L689I) occurring in the linker DIIS4-S5 and its functional expression in a mammalian system. Objective To correlate the clinical manifestations of hyperkalemic periodic paralysis (hyperKPP) with the functional expression of a sodium… 

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  • N. YangS. Ji A. George
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1994
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Defective slow inactivation of sodium channels contributes to familial periodic paralysis

SI is defective in a subset of mutant Na channels associated with episodic weakness (HyperPP or PMC) but remains intact for mutants studied so far that cause myotonia without weakness (PAM).

Sodium channel mutations in acetazolamide‐responsive myotonia congenita, paramyotonia congenita, and hyperkalemic periodic paralysis

This report summarizes the sodium channel mutation analysis in 25 families with hyperKPP and reports the putative disease-causing mutation in acetazolamide-responsiveMyotonia congenita, a related disease in which myotonia is worsened by potassium but in which episodic weakness does not occur.