Tension produced by a contracting muscle results from cycling interaction of myosin cross-bridges with actin filaments using the energy of ATP hydrolysis. A number of kinetic models and schemes of mechanical and biochemical processes in actin-myosin cycle of interaction have been developed during the last 50 years. However there are some experimental facts that cannot be reproduced by existing models. The aim of the work is to develop a program complex for computer simulation of kinetic models of muscle contraction with different numbers of attached and detached states of cross-bridges and the possibility of construction of different rates for transitions from one state to another. Some blocks of software already allow one to calculate biochemical and mechanical characteristics of muscle fibres during isometric contraction and steady-state shortening and we suggest a model which include 3 detached and 7 attached states based on the «roll and lock» model (Ferenczi et al., Structure, 2005). The results of simulation of experiments with isometric contraction and steady-state shortening of muscle fibres describes observed data for the dependence of fiber tension, stiffness and ATPase rate on concentrations of ATP, ADP and inorganic phospate at different temperatures.
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