کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2070225 1078476 2011 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A theory on auto-oscillation and contraction in striated muscle
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیوفیزیک
پیش نمایش صفحه اول مقاله
A theory on auto-oscillation and contraction in striated muscle
چکیده انگلیسی

It is widely accepted that muscle cells take either force-generating or relaxing state in an all-or-none fashion through the so-called excitation–contraction coupling. On the other hand, the membrane-less contractile apparatus takes the third state, i.e., the auto-oscillation (SPOC) state, at the activation level that is intermediate between full activation and relaxation. Here, to explain the dynamics of all three states of muscle, we construct a novel theoretical model based on the balance of forces not only parallel but also perpendicular to the long axis of myofibrils, taking into account the experimental fact that the spacing of myofilament lattice changes with sarcomere length and upon contraction. This theory presents a phase diagram composed of several states of the contractile apparatus and explains the dynamic behavior of SPOC, e.g., periodical changes in sarcomere length with the saw-tooth waveform. The appropriate selection of the constant of the molecular friction due to the cross-bridge formation can explain the difference in the SPOC periods observed under various activating conditions and in different muscle types, i.e., skeletal and cardiac. The theory also predicts the existence of a weak oscillation state at the boundary between SPOC and relaxation regions in the phase diagram. Thus, the present theory comprehensively explains the characteristics of auto-oscillation and contraction in the contractile system of striated muscle.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Progress in Biophysics and Molecular Biology - Volume 105, Issue 3, May 2011, Pages 199–207
نویسندگان
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