Evaluation of frequency, type, and function of gap junctions between skeletal myoblasts overexpressing connexin43 and cardiomyocytes: relevance to cell transplantation

• Published in: The FASEB journal 2006-04, Vol.20 (6), p.744-746
• Main Authors: Stagg, Mark A, Coppen, Steven R, Suzuki, Ken, Varela-Carver, Anabel, Lee, Joon, Brand, Nigel J, Fukushima, Satsuki, Yacoub, Magdi H, Terracciano, Cesare M. N
• Format: Article
• Language: English
• Subjects: Animals; Cell Communication; Cell Transplantation; Cells, Cultured; Coculture Techniques; Connexin 43 - metabolism; Electric Conductivity; electrophysiology; gap junctional conductance; Gap Junctions - physiology; Male; Mice; Myoblasts, Skeletal - metabolism; Myocytes, Cardiac - metabolism; Rats; Rats, Sprague-Dawley
• ISSN: 1530-6860; 0892-6638; 1530-6860
• DOI: 10.1096/fj.05-5088fje

ABSTRACT Cell transplantation of skeletal myoblasts (SMs) is one possible treatment for repairing cardiac tissue after myocardial injury. However, inappropriate electrical coupling between grafted SMs and host cardiomyocytes may be responsible for the arrhythmias observed in clinical trials of SM transplantation. Whether functional gap junctions occur between the two cell types remains controversial. We have studied the ability of SMs to electrically couple with isolated adult rat cardiomyocytes (CMs) and assessed whether connexin43 (Cx43) overexpression enhanced gap junctional conductance (Gj). C2C12 myoblast lines overexpressing Cx43 were generated by gene transfection and clonal selection. CMs were cocultured with either SMs overexpressing Cx43 (CM‐SMCx43) or control SMs (CM‐SMWT) in vitro. Gj between pairs of SMs and CMs was quantified with dual whole cell patch clamping. Formation of Gj occurred between 22% of CM‐SMWT pairs (n=73) and 48% of CM‐SMCx43 pairs (n=71, P