Intracellular calcium movements during excitation–contraction coupling in mammalian slow-twitch and fast-twitch muscle fibers
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منابع مشابه
Intracellular calcium movements during excitation–contraction coupling in mammalian slow-twitch and fast-twitch muscle fibers
In skeletal muscle fibers, action potentials elicit contractions by releasing calcium ions (Ca(2+)) from the sarcoplasmic reticulum. Experiments on individual mouse muscle fibers micro-injected with a rapidly responding fluorescent Ca(2+) indicator dye reveal that the amount of Ca(2+) released is three- to fourfold larger in fast-twitch fibers than in slow-twitch fibers, and the proportion of t...
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An apparatus is described which collects the effluent from the center 0.7 cm of a single muscle fiber or bundle of muscle fibers. It was used to study the efflux of (45)Ca from twitch muscle fibers. The efflux can be described by three time constants 18 +/- 2 min, 300 +/- 40 min, and 882 +/- 172 min. These kinetics have been interpreted as those of a three-compartment system. The fastest is tho...
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ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 2012
ISSN: 1540-7748,0022-1295
DOI: 10.1085/jgp.201210773