Hypokalemic periodic paralysis: In vitro investigation of muscle fiber membrane parameters

@article{Rudel1984HypokalemicPP,
  title={Hypokalemic periodic paralysis: In vitro investigation of muscle fiber membrane parameters},
  author={Reinhardt Rüdel and Frank Lehmann-Horn and Kenneth Ricker and Gerald K{\"u}ther},
  journal={Muscle \& Nerve},
  year={1984},
  volume={7}
}
To study the mechanism of attacks in familial hypokalemic paralysis, we recorded resting membrane potentials, action potentials, current–voltage relationships, and isometric forces in intercostal muscle fibers from three patients. In normal extracellular medium, the resting potential was reduced, but membrane conductance was not different from control. Excitability was reduced and the action potentials had no overshoot. On exposure to a 1‐mM potassium solution, with or without insulin, the… Expand
Insulin acts in hypokalemic periodic paralysis by reducing inward rectifier K+ current.
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  • Chemistry, Medicine
  • Neurology
  • 1999
TLDR
Insulin potentiates depolarization of hypokalemic periodic paralysis (HypoPP) fibers by reducing inward rectifier K+ conductance and indirectly derange membrane excitability by altering the function of other membrane channels. Expand
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  • R. Ruff
  • Biology, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 2000
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This issue defined some of the abnormalities in surface membrane ionic currents that are responsible for the phenotype of HypoPP and described five families, each of which had one of two mutations Arg-672→His or Arg-674→Gly. Expand
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  • Chemistry, Medicine
  • Neurology
  • 2011
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The electrical instability of the membrane and the transient weakness can be explained on the basis of the N‐shaped membrane characteristic. Expand
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