Haraguchi Yuji
   Department   Research Institutes and Facilities, Research Institutes and Facilities
   Position   Associate Professor (Fixed Term)
Article types Original article
Language English
Peer review Peer reviewed
Title Electrical coupling of cardiomyocyte sheets occurs rapidly via functional gap junction formation.
Journal Formal name:Biomaterials
ISSN code:(0142-9612)0142-9612(Linking)
Domestic / ForeginForegin
Volume, Issue, Page 27(27),pp.4765-74
Author and coauthor Haraguchi Yuji†, Shimizu Tatsuya, Yamato Masayuki, Kikuchi Akihiko, Okano Teruo*
Authorship Lead author
Publication date 2006/09
Summary Previously, we have successfully created pulsatile myocardial tissue grafts using our novel technology, "cell sheet engineering", that layers cell sheets fabricated on temperature-responsive culture dishes to form three-dimensional (3-D) structures. Electrical coupling is established between layered neonatal rat cardiomyocyte sheets, resulting in the synchronized beating of 3-D myocardial tissues. However, the mechanism by which these layered cardiomyocyte sheets communicate electrically is not well-understood. In this study, we used a multiple-electrode extracellular recording system and demonstrated that bilayer cardiomyocyte sheets coupled electrically with slight delays 34+/-2 min (mean+/-SEM) after layering. These delays gradually decreased and the electrical actions of layered cell sheets were completely coupled 46+/-3 min (mean+/-SEM) after initial layering. Immunohistological analysis showed that connexin43, a gap junction (GJ)-related protein, existed not only at cell-to-cell interfaces but also on the free cell membrane in the cardiomyocyte sheet. Additionally, neither connexin40 nor connexin45, but only connexin43 was detected between bilayer cardiomyocyte sheets within 30 min after layering. Dye transfer assay demonstrated that the exchange of small molecules via GJs occurred within 30 min. The cell sheet manipulation technique using the temperature-responsive culture dishes has substantial advances and the exciting potential in the fields of cell and tissue physiology, as well as tissue engineering.
DOI 10.1016/j.biomaterials.2006.04.034
PMID 16737736