To the problem of cross-bridge tension in steady muscle shortening and lengthening

Valery B. Kokshenev

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arXiv · 0909.0687

To the problem of cross-bridge tension in steady muscle shortening and lengthening

Valery B. Kokshenev

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Abstract

Despite the great success of the Huxley sliding filament model proposed half a century ago for actin-myosin linkages (cross-bridges), it fails to explain the force-velocity behavior of stretching skeletal muscles. Huxley's two-state kinetic equation for cross-bridge proportions is therefore reconsidered and a new solution to the problem of steady muscle eccentric and concentric contractions is reported. When the second law of statistical thermodynamics is applied to cross-bridge proportions, the weakly bound states appear to be correlated to the strongly bound states via structural and kinetic intrinsic muscle characteristics. The explicit force-velocity curve fits the empirical tension-velocity data on frog muscle shortening using only one adjustable parameter, while the Huxley model employed four parameters.

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Valery B. Kokshenev. 2009-09-03. To the problem of cross-bridge tension in steady muscle shortening and lengthening. https://arxiv.org/abs/0909.0687

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