Fluctuations in polarized fluorescence: evidence that muscle cross bridges rotate repetitively during contraction.
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چکیده
منابع مشابه
Fluctuations in polarized fluorescence: evidence that muscle cross bridges rotate repetitively during contraction.
Particular thiols of the myosin subfragment 1 moieties of single glycerinated muscle fibers are covalently labeled with rhodamine. By using appropriate solutions such fibers can be relaxed, be in rigor, or develop active isometric tension. The rhodamine is excited by polarized 514.5-nm laser light; the greater than 580-nm fluorescence is resolved into orthogonal components and the intensity of ...
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The method of polarized fluorescence depletion (PFD) has been applied to enhance the resolution of orientational distributions and dynamics obtained from fluorescence polarization (FP) experiments on ordered systems, particularly in muscle fibers. Previous FP data from single fluorescent probes were limited to the 2(nd)- and 4(th)-rank order parameters, and , of...
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We have searched for fluctuations in the steady-state tension developed by stimulated single muscle fibers. Such tension "noise" is expected to be present as a result of the statistical fluctuations in the number and/or state of myosin cross-bridges interacting with thin filament sites at any time. A sensitive electro-optical tension transducer capable of resolving the expected fluctuations in ...
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Contraction of detrusor smooth muscle (DSM) at short muscle lengths generates a stiffness component we termed adjustable passive stiffness (APS) that is retained in tissues incubated in a Ca(2+)-free solution, shifts the DSM length-passive tension curve up and to the left, and is softened by muscle strain and release (strain softened). In the present study, we tested the hypothesis that APS is ...
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It is generally believed that cross bridges account for >50% of the total ATP consumed by skeletal muscle during contraction. We investigated the effect of N-benzyl-p-toluene sulfonamide (BTS), an inhibitor of myosin ATPase, on muscle force production and energy metabolism under near-physiological conditions (50-Hz stimulation frequency at 30 degrees C results in 35% of maximal force). Extensor...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1979
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.76.12.6346