Transient weakness and altered membrane characteristic in recessive generalized myotonia (Becker)

@article{Rudel1988TransientWA,
  title={Transient weakness and altered membrane characteristic in recessive generalized myotonia (Becker)},
  author={Reinhardt Rüdel and Kenneth Ricker and Frank Lehmann-Horn},
  journal={Muscle \& Nerve},
  year={1988},
  volume={11}
}
The isometric force of arm and leg muscles was studied in five unrelated patients with recessive generalized myotonia (Becker). The symptom of myotonia was present mainly in the legs, whereas transient weakness was the prominent symptom in the arms. Tocainide improved both symptoms, although it improved the stiffness more than the weakness. A specimen of intact muscle fibers was excised from the external intercostal muscle of one of the patients. The resting potential of the fibers was normal… 
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81 Citations

Abnormalities of the fast sodium current in myotonic dystrophy, recessive generalized myotonia, and adynamia episodica
TLDR
C cultured from the biopsied muscles of patients with myotonic dystrophy, three patients with recessive generalized myotonia, and a patient with adynamia episodica, the time constants of activation and inactivation showed a characteristic pattern of abnormalities.
The mechanism underlying transient weakness in myotonia congenita
TLDR
Transient weakness in myotonia congenita is caused by depolarization secondary to activation of persistent Na+ current in skeletal muscle, and targeting NaPIC with ranolazine prevents the development of plateau potentials and eliminates transient weakness in vivo.
Altered sodium channel behaviour causes myotonia in dominantly inherited myotonia congenita
Altered Na+ channel activity and reduced Cl− conductance cause hyperexcitability in recessive generalized myotonia (becker)
TLDR
It is concluded that a combination of reduced Cl− conductance and the reopenings of Na+ channels underlie the electrical afteractivity in recessive generalized myotonia.
Myotonic disorders.
Propagation disturbance of motor unit action potentials during transient paresis in generalized myotonia: a high-density surface EMG study.
TLDR
It is concluded that the transient paresis is explained by a deteriorating muscle membrane function, ending in conduction block and pareis, and shows how spatiotemporal information, available through non-invasive high-density sEMG, may provide novel insights into electrophysiological aspects of membrane dysfunction.
Schwartz–Jampel syndrome: II. Na+ channel defect causes myotonia
TLDR
It is hypothesized that altered membrane conductances are responsible for the hyperexcitability and the associated slowed relaxation in skeletal muscle fibers from a patient with Schwartz–Jampel syndrome.
Muscle channelopathies. Myotonias and periodic paralyses
Myotonia and the muscle chloride channel
TLDR
Clinical and molecular data show that dominantly inherited Thomsen's myotonia is most often a very mild disorder that shows considerable clinical heterogeneity, and one Italian family is shown to have a novel dominant mutation--I290M.
Transient weakness and compound muscle action potential decrement in myotonia congenita
Twenty‐five Turkish patients with recessive myotonia congenita (RMC), 16 of whom had genetic confirmation, were studied. Nineteen had transient weakness. In the upper extremities, onset age of…
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