Skip to Main content Skip to Navigation
Journal articles

Regional variation in myofilament length-dependent activation.

Abstract : The Frank-Starling law is an important regulatory mechanism of the heart that links the end-diastolic volume with the systolic ejection fraction. This beat-to-beat regulation of the heart, underlined at the cellular level by higher myofilament calcium sensitivity at longer sarcomere length, is known as length-dependent activation or stretch sensitization of activation. However, the heart is structurally and functionally heterogeneous and asymmetrical. Specifically, contractile properties are not uniform within the left ventricle partly due to transmural differences in action potential waveforms and calcium homeostasis. The present review will focus on the role of the contractile machinery in the transmural contractile heterogeneity and its adaptation to changes in muscle strain. The expression of different myosin isoforms, the level of titin-based passive tension, and thin and thick sarcomeric regulatory proteins are considered to explain the regional cellular contractile properties. Finally, the importance of transmural heterogeneity of length-dependent activation and the consequences of its modification on the heart mechanics are discussed. Despite extensive research since the characterization of the Frank-Starling law, the molecular mechanisms by which strain information is transduced to the contractile machinery have not been fully determined yet.
Complete list of metadata

Cited literature [104 references]  Display  Hide  Download
Contributor : Olivier Cazorla Connect in order to contact the contributor
Submitted on : Thursday, March 3, 2011 - 11:29:00 AM
Last modification on : Friday, August 5, 2022 - 10:52:32 AM
Long-term archiving on: : Saturday, December 3, 2016 - 11:09:02 PM


 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : jamais

Please log in to resquest access to the document




Olivier Cazorla, Alain Lacampagne. Regional variation in myofilament length-dependent activation.. Pflügers Archiv European Journal of Physiology, Springer Verlag, 2011, 462 (1), pp.15-28. ⟨10.1007/s00424-011-0933-6⟩. ⟨inserm-00573260⟩



Record views