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

✍ Scribed by Ewa Nurowska; Andrew Constanti; Beata Dworakowska; Vincent Mouly; Denis Furling; Paola Lorenzon; Tiziana Pietrangelo; Krzysztof Dołowy; Fabio Ruzzier

• Book ID: 111490455
• Publisher: SP Versita
• Year: 2009
• Tongue: English
• Weight: 633 KB
• Volume: 14
• Category: Article
• ISSN: 1425-8153
• DOI: 10.2478/s11658-009-0006-4

✦ Synopsis

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.