Extreme sarcoplasmic reticulum volume loss and compensatory T-tubule remodeling after Serca2 knockout.

Proceedings of the National Academy of Sciences of the United States of America
Fredrik SwiftWilliam E Louch

Abstract

Cardiomyocyte contraction and relaxation are controlled by Ca(2+) handling, which can be regulated to meet demand. Indeed, major reduction in sarcoplasmic reticulum (SR) function in mice with Serca2 knockout (KO) is compensated by enhanced plasmalemmal Ca(2+) fluxes. Here we investigate whether altered Ca(2+) fluxes are facilitated by reorganization of cardiomyocyte ultrastructure. Hearts were fixed for electron microscopy and enzymatically dissociated for confocal microscopy and electrophysiology. SR relative surface area and volume densities were reduced by 63% and 76%, indicating marked loss and collapse of the free SR in KO. Although overall cardiomyocyte dimensions were unaltered, total surface area was increased. This resulted from increased T-tubule density, as revealed by confocal images. Fourier analysis indicated a maintained organization of transverse T-tubules but an increased presence of longitudinal T-tubules. This demonstrates a remarkable plasticity of the tubular system in the adult myocardium. Immunocytochemical data showed that the newly grown longitudinal T-tubules contained Na(+)/Ca(2+)-exchanger proximal to ryanodine receptors in the SR but did not contain Ca(2+)-channels. Ca(2+) measurements demonstrated ...Continue Reading

References

Mar 16, 2006·Proceedings of the National Academy of Sciences of the United States of America·Long-Sheng SongHeping Cheng
Jun 19, 2007·Journal of Molecular and Cellular Cardiology·Halvor K MørkWilliam E Louch
Mar 31, 2009·Journal of Molecular and Cellular Cardiology·Kristin Brevik AnderssonGeir Christensen
Dec 17, 2009·The Journal of Physiology·William E LouchOle M Sejersted
Jun 26, 2010·Circulation Research·Sheng WeiLong-Sheng Song

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Citations

Jul 27, 2012·Cardiovascular Research·Fredrik Swift, Geir Christensen
Jan 25, 2013·Cardiovascular Research·Michael Ibrahim, Cesare M Terracciano
Jan 16, 2014·Interface Focus·Sander LandNicolas P Smith
Jul 31, 2012·American Journal of Physiology. Cell Physiology·Christopher H GeorgeNicole C Silvester
Mar 1, 2013·The Journal of Neuroscience : the Official Journal of the Society for Neuroscience·Kathryn H CondonMichael D Ehlers
Feb 9, 2013·Cardiovascular Research·Ang GuoLong-Sheng Song
Jun 19, 2014·Biophysical Journal·Ang Guo, Long-Sheng Song
Feb 3, 2015·The Journal of Physiology·William E LouchPasi Tavi
Jun 19, 2013·Journal of Molecular and Cellular Cardiology·J M AronsenO M Sejersted
Mar 27, 2013·Biophysical Journal·Sander LandNicolas P Smith
May 12, 2016·Heart Failure Reviews·George H KunkelSuresh C Tyagi
May 27, 2016·Cardiovascular Research·Michael FriskWilliam E Louch
Nov 25, 2016·Physiological Reviews·TingTing Hong, Robin M Shaw
May 5, 2017·Clinical Medicine Insights. Cardiology·Andrew G Edwards, William E Louch
Mar 29, 2014·Nature·Christine WahlquistMark Mercola
Feb 2, 2019·The Journal of Physiology·D B LipsettW E Louch
Jun 22, 2014·American Journal of Physiology. Heart and Circulatory Physiology·Michael FriskWilliam E Louch
Jan 9, 2019·Frontiers in Physiology·Peter P JonesWilliam E Louch
Apr 28, 2017·Current Heart Failure Reports·Ornella ManfraWilliam E Louch
Oct 24, 2020·The Korean Journal of Physiology & Pharmacology : Official Journal of the Korean Physiological Society and the Korean Society of Pharmacology·Sun Hwa ParkTong Mook Kang
Oct 30, 2021·Frontiers in Physiology·Andrew G EdwardsWilliam E Louch

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