Differential contribution of cardiac sarcomeric proteins in the myofibrillar force response to stretch

Abstract : The present study examined the contribution of myofilament contractile proteins to regional function in guinea pig myocardium. We investigated the effect of stretch on myofilament contractile proteins, Ca 2+ sensitivity, and cross-bridge cycling kinetics (K tr) of force in single skinned cardiomyocytes isolated from the sub-endocardial (ENDO) or sub-epicardial (EPI) layer. As observed in other species, ENDO cells were stiffer, and Ca 2+ sensitivity of force at long sarcomere length was higher compared with EPI cells. Maximal K tr was unchanged by stretch, but was higher in EPI cells possibly due to a higher α-MHC content. Submaximal Ca 2+-activated K tr increased only in ENDO cells with stretch. Stretch of skinned ENDO muscle strips induced increased phosphorylation in both myosin-binding protein C and myosin light chain 2. We concluded that transmural MHC isoform expression and differential regulatory protein phosphorylation by stretch contributes to regional differences in stretch modulation of activation in guinea pig left ventricle.
Liste complète des métadonnées

Littérature citée [50 références]  Voir  Masquer  Télécharger

https://hal.umontpellier.fr/hal-01824379
Contributeur : Olivier Cazorla <>
Soumis le : mardi 3 juillet 2018 - 14:59:31
Dernière modification le : mercredi 4 juillet 2018 - 01:05:18

Lien texte intégral

Identifiants

Collections

Citation

Younss Ait Mou, Jean-Yves Le Guennec, Emilio Mosca, Pieter De Tombe, Olivier Cazorla. Differential contribution of cardiac sarcomeric proteins in the myofibrillar force response to stretch. Pflügers Archiv European Journal of Physiology, Springer Verlag (Germany), 2008, 457 (1), pp.25 - 36. 〈10.1007/s00424-008-0501-x〉. 〈hal-01824379〉

Partager

Métriques

Consultations de la notice

8