Ca²⁺ and force during dynamic contractions in mouse intact skeletal muscle fibers.

ABSTRACT: Muscle fiber force production is determined by the excitation frequency of motor nerves, which induce transient increases in cytoplasmic free Ca²⁺ concentration ([Ca²⁺]_i) and the force-generating capacity of the actomyosin cross-bridges. Previous studies suggest that, in addition to altered cross-bridge properties, force changes during dynamic (concentric or eccentric) contraction might be affected by Ca²⁺-dependent components. Here we investigated this by measuring [Ca²⁺]_i and force in mouse muscle fibers undergoing isometric, concentric, and eccentric contractions. Intact single muscle fibers were dissected from the flexor digitorum brevis muscle of mice. Fibers were electrically activated isometrically at 30-100 Hz and af

SUBMITTER: Fukutani A 

PROVIDER: S-EPMC10771458 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature