Tension, stiffness, unloaded shortening speed and potentiation of frog muscle fibres at sarcomere lengths below optimum.
نویسندگان
چکیده
منابع مشابه
The Ultrastructure of Striated Muscle at Various Sarcomere Lengths
1. Rest and equilibrium length muscle sarcomeres are composed of thin filaments (actin) which traverse the sarcomeres from the Z membranes up to the H band; at this level the filaments are considerably thicker and less numerous. 2. Shortening of muscle is associated with a transformation of thin into thick filaments in the A band. 3. These observations are discussed in terms of interaction of a...
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A new technique permits removal of the resting force from the muscle during the course of shortening and study of the maximum velocity of shortening with almost zero load at physiological initial muscle lengths. This unloading has been performed as a sudden unloading to zero total load (zero load clamping), or according to the resting length-tension relations, or according to an arbitrary unloa...
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The relation between shortening heat and sarcomere length was studied using fiber bundles from frog semitendinosus muscles as well as using whole muscles. The initial sarcomere length was varied between 2.0 and 3.66 micron. Shortening heat was estimated as the excess heat produced after a rapid isovelocity release in a 3 sec tetanus at 0 degrees C. The isometric control heat was measured in the...
متن کاملFrog Chemically Skinned Atrial Myocytes and in Mechanically Disrupted Ventricular Myocardium From Rat
Effects of [Ca211 on isometric tension and unloaded shortening velocity were characterized in single chemically skinned myocytes from frog atrium and in mechanically disrupted myocardium from rat ventricle. The preparations were attached to a force transducer and piezoelectric translator and were viewed with an inverted microscope to allow continuous monitoring of sarcomere length during mechan...
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Effects of [Ca2+] on isometric tension and unloaded shortening velocity were characterized in single chemically skinned myocytes from frog atrium and in mechanically disrupted myocardium from rat ventricle. The preparations were attached to a force transducer and piezoelectric translator and were viewed with an inverted microscope to allow continuous monitoring of sarcomere length during mechan...
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ژورنال
عنوان ژورنال: The Journal of Physiology
سال: 1981
ISSN: 0022-3751
DOI: 10.1113/jphysiol.1981.sp013902