Open Access

Potassium currents in human myogenic cells from healthy and congenital myotonic dystrophy foetuses

  • Ewa Nurowska1Email author,
  • Andrew Constanti2,
  • Beata Dworakowska1,
  • Vincent Mouly3,
  • Denis Furling3,
  • Paola Lorenzon4,
  • Tiziana Pietrangelo4, 5,
  • Krzysztof Dołowy1 and
  • Fabio Ruzzier4
Cellular & Molecular Biology LettersAn International Journal200914:6

DOI: 10.2478/s11658-009-0006-4

Received: 4 July 2008

Accepted: 23 January 2009

Published: 4 February 2009

Abstract

The whole-cell patch clamp technique was used to record potassium currents in in vitro differentiating myoblasts isolated from healthy and myotonic dystrophy type 1 (DM1) foetuses carrying 2000 CTG repeats. The fusion of the DM1 myoblasts was reduced in comparison to that of the control cells. The dystrophic muscle cells expressed less voltage-activated K+ (delayed rectifier and non-inactivating delayed rectifier) and inward rectifier channels than the age-matched control cells. However, the resting membrane potential was not significantly different between the control and the DM1 cells. After four days in a differentiation medium, the dystrophic cells expressed the fast-inactivating transient outward K+ channels, which were not observed in healthy cells. We suggest that the low level of potassium currents measured in differentiated DM1 cells could be related to their impaired fusion.

Key words

Potassium channels Myoblast fusion Congenital myotonic dystrophy Patch-clamp

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