Species differences in the morphology of transverse tubule openings in cardiomyocytes

Abstract: Aims
The ultrastructure of ventricular cardiomyocyte T-tubule connections with the outer cell surface (‘mouth’ regions) has been reported to differ between mice and rabbits. In mice, T-tubule mouths form convoluted narrow spaces filled with electron-dense matter that impedes diffusion between T-tubular lumen and bulk extracellular space. Here, we explore whether T-tubule mouths are also constricted in rat (another murine model used frequently for cardiac research) and whether pig and human T-tubule mouth configurations are structurally more similar to mice or rabbits.

Methods and results
We used chemically-fixed tissue and high-pressure frozen isolated cardiomyocytes to compare T-tubule mouth architecture using transmission electron microscopy and three-dimensional electron tomography. We find that rat T-tubular mouth architecture is more similar to that of rabbits than mice, lacking the marked tortuosity and electron-dense ground substance that obstructs access to deeper portions of the T-tubular system in mice. Pilot observations in larger mammals (pig, human) suggest that mouse may be the least representative animal model of T-tubule connectivity with the outer cell surface in larger mammals.

Conclusion
Rat T-tubular system architecture appears to be more similar in size and topology to larger mammals than mice. T-tubular mouth topology may contribute to differences in experimental model behaviour, underscoring the challenge of appropriate model selection for research into cell and tissue function

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: EP Europace. - 20, Suppl_3 (2018) , iii120-iii124, ISSN: 1099-5129

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2019
• Creator: Rog-Zielinska, Eva Alicja ; Kong, Cherrie Hei Ting ; Zgierski-Johnston, Callum M. ; Verkade, Paul ; Mantell, Judith ; Cannell, Mark Bryden ; Kohl, Peter
• Contributor: Institut für Experimentelle Kardiovaskuläre Medizin

Further information

• DOI: 10.1093/europace/euy245
• URN: urn:nbn:de:bsz:25-freidok-1473068
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 25.03.2025, 1:56 PM CET