%0 Journal Article %1 tracqui-ohayon %A Tracqui, Philippe %A Ohayon, Jacques %C 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND %D 2009 %I ROYAL SOC %J PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES %K calcium force heart %N 1908 %P 4887-4905 %R 10.1098/rsta.2009.0149 %T An integrated formulation of anisotropic force-calcium relations driving spatio-temporal contractions of cardiac myocytes %V 367 %X Isolated cardiac myocytes exhibit spontaneous patterns of rhythmic contraction, driven by intracellular calcium waves. In order to study the coupling between spatio-temporal calcium dynamics and cell contraction in large deformation regimes, a new strain-energy function, describing the influence of sarcomere length on the calcium-dependent generation of active intracellular stresses, is proposed. This strain-energy function includes anisotropic passive and active contributions that were first validated separately from experimental stress-strain curves and stress-sarcomere length curves, respectively. An extended validation of this formulation was then conducted by considering this strain-energy function as the core of an integrated mechano-chemical three-dimensional model of cardiac myocyte contraction, where autocatalytic intracellular calcium dynamics were described by a representative two-variable model able to generate realistic intracellular calcium waves similar to those observed experimentally. Finite-element simulations of the three-dimensional cell model, conducted for different intracellular locations of triggering calcium sparks, explained very satisfactorily, both qualitatively and quantitatively, the contraction patterns of cardiac myocytes observed by time-lapse videomicroscopy. This integrative approach of the mechano-chemical couplings driving cardiac myocyte contraction provides a comprehensive framework for analysing active stress regulation and associated mechano-transduction processes that contribute to the efficiency of cardiac cell contractility in both physiological and pathological contexts.

@article{tracqui-ohayon, abstract = {{Isolated cardiac myocytes exhibit spontaneous patterns of rhythmic contraction, driven by intracellular calcium waves. In order to study the coupling between spatio-temporal calcium dynamics and cell contraction in large deformation regimes, a new strain-energy function, describing the influence of sarcomere length on the calcium-dependent generation of active intracellular stresses, is proposed. This strain-energy function includes anisotropic passive and active contributions that were first validated separately from experimental stress-strain curves and stress-sarcomere length curves, respectively. An extended validation of this formulation was then conducted by considering this strain-energy function as the core of an integrated mechano-chemical three-dimensional model of cardiac myocyte contraction, where autocatalytic intracellular calcium dynamics were described by a representative two-variable model able to generate realistic intracellular calcium waves similar to those observed experimentally. Finite-element simulations of the three-dimensional cell model, conducted for different intracellular locations of triggering calcium sparks, explained very satisfactorily, both qualitatively and quantitatively, the contraction patterns of cardiac myocytes observed by time-lapse videomicroscopy. This integrative approach of the mechano-chemical couplings driving cardiac myocyte contraction provides a comprehensive framework for analysing active stress regulation and associated mechano-transduction processes that contribute to the efficiency of cardiac cell contractility in both physiological and pathological contexts.}}, added-at = {2013-01-07T13:43:43.000+0100}, address = {{6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND}}, affiliation = {{Tracqui, P (Reprint Author), Univ Grenoble 1, Lab Tech Ingn Med \& Complex Informat Math Applica, Equipe DynaCell, Unite Mixte Rech,Fac Med Grenoble,In3S,CNRS 5525, F-38706 La Tronche, France.. Tracqui, Philippe; Ohayon, Jacques, Univ Grenoble 1, Lab Tech Ingn Med \& Complex Informat Math Applica, Equipe DynaCell, Unite Mixte Rech,Fac Med Grenoble,In3S,CNRS 5525, F-38706 La Tronche, France.}}, author = {Tracqui, Philippe and Ohayon, Jacques}, author-email = {{philippe.tracqui@imag.fr}}, biburl = {https://www.bibsonomy.org/bibtex/27b1fb4b5a5bc12a0c96b8bd4e5ab7942/jehiorns}, doc-delivery-number = {{513OP}}, doi = {{10.1098/rsta.2009.0149}}, funding-acknowledgement = {{IXXI Institut Rhone-Alpin des Systemes Complexes}}, funding-text = {{We thank Dr J. Olivares (LBFA-UJF, Grenoble, France) for providing isolated cardiomyocytes. This work is supported by a grant from IXXI Institut Rhone-Alpin des Systemes Complexes.}}, interhash = {208670e10a6e161700352cd509a6cf40}, intrahash = {7b1fb4b5a5bc12a0c96b8bd4e5ab7942}, issn = {{1364-503X}}, journal = {{PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES}}, journal-iso = {{Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci.}}, keywords = {calcium force heart}, keywords-plus = {{SPIRAL CA2+ WAVES; FINITE-ELEMENT-METHOD; SARCOPLASMIC-RETICULUM; CONSTITUTIVE RELATION; COMPUTATIONAL MODEL; PASSIVE MYOCARDIUM; SARCOMERE-LENGTH; ATRIAL MYOCYTES; OSCILLATIONS; RELEASE}}, language = {{English}}, month = {{DEC 13}}, number = {{1908}}, number-of-cited-references = {{51}}, pages = {{4887-4905}}, publisher = {{ROYAL SOC}}, research-areas = {{Science \& Technology - Other Topics}}, times-cited = {{1}}, timestamp = {2013-01-07T13:43:43.000+0100}, title = {{An integrated formulation of anisotropic force-calcium relations driving spatio-temporal contractions of cardiac myocytes}}, type = {{Article}}, unique-id = {{ISI:000271332700013}}, volume = {{367}}, web-of-science-categories = {{Multidisciplinary Sciences}}, year = {{2009}} }