A Cross-Bridge Model Describing the Mechanoenergetics of Actomyosin Interaction
In order to study the mechanical contraction and energy consumption by the cardiomyocytes we further developed an actomyosin model of Vendelin et al. (Ann. Biomed. Eng. 28:629–640, 2000). The model is of a self-consistent Huxley-type and is based on Hill formalism linking the free energy profile of reactions and mechanical force. In several experimental studies it has been shown that the dependency between oxygen consumption and stress-strain area is linear and is the same for isometric and shortening contractions. We analyzed the free energy profiles of actomyosin interaction by changing free energies of intermediate states and activation of different reactions. The model is able to replicate the linear dependence between oxygen consumption and stress-strain area together with other important mechanical properties of a cardiac muscle.
KeywordsIsometric Contraction Myosin Head Biochemical State Mechanical Contraction Free Energy Profile
This research was supported by the European Union through the European Regional Development Fund and by the Estonian Science Foundation (Grant nr. 7344).
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