Related Experiment Video
Updated: Aug 9, 2026

Assessment of Calcium Sparks in Intact Skeletal Muscle Fibers
Published on: February 24, 2014
Calcium transients and intramembrane charge movement in skeletal muscle fibres
Abstract:
Myoplasmic calcium transients in response to pulse depolarisations have been monitored using the dye antipyralazo III, which provides a linear measure of the change in cytoplasmic free calcium concentration. Intramembrane charge movements were recorded simultaneously with the calcium transients. Except for its initial phase, the calcium transient during each pulse closely followed the time course expected for calcium redistribution between three intracellular compartments with time-independent flux coefficients. The time at which the flux coefficients attained their steady values occurred just after the intramembrane charge movement had been completed. This is the required sequence if charge movement were to control one or more coefficients f or calcium fluxes across the sarcoplasmic reliculum membrane.
Related Concept Videos
Cross-bridge Cycle
Overview of Skeletal Muscle
Generation of Action Potential in Skeletal Muscles
Like neurons, muscle cells are also regarded as excitable due to their capacity to change in response to stimuli, primarily due to voltage-gated ion channels embedded in their plasma membranes, which get activated by alterations in the cell's...
Excitation-Contraction Coupling in Skeletal Muscles
When an action potential...
Relaxation of Skeletal Muscles
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
Smooth Muscle Contraction
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...

