Related Experiment Video

Updated: Aug 19, 2026

Assessment of Calcium Sparks in Intact Skeletal Muscle Fibers
11:22

Assessment of Calcium Sparks in Intact Skeletal Muscle Fibers

Published on: February 24, 2014

Mechanism of calcium release from skeletal sarcoplasmic reticulum

H Miyamoto, E Racker

    The Journal of Membrane Biology
    |January 1, 1982
    PubMed

    More Related Videos

    Measurement of Calcium Fluctuations Within the Sarcoplasmic Reticulum of Cultured Smooth Muscle Cells Using FRET-based Confocal Imaging10:05

    Measurement of Calcium Fluctuations Within the Sarcoplasmic Reticulum of Cultured Smooth Muscle Cells Using FRET-based Confocal Imaging

    Published on: June 20, 2016

    Monitoring ER/SR Calcium Release with the Targeted Ca2+ Sensor CatchER+12:30

    Monitoring ER/SR Calcium Release with the Targeted Ca2+ Sensor CatchER+

    Published on: May 19, 2017

    Related Concept Videos

    Cross-bridge Cycle01:26

    Cross-bridge Cycle

    As muscle contracts, the overlap between the thin and thick filaments increases, decreasing the length of the sarcomere—the contractile unit of the muscle—using energy in the form of ATP. At the molecular level, this is a cyclic, multistep process that involves binding and hydrolysis of ATP, and movement of actin by myosin.
    Overview of Skeletal Muscle01:15

    Overview of Skeletal Muscle

    Skeletal muscles are composed of a bundle of muscle fibers and are attached to bones through tendons. Each skeletal muscle fiber is a single muscle cell. The sarcolemma, the plasma membrane of a skeletal muscle cell, consists of a lipid bilayer and glycocalyx that supports muscle fibers. The sarcolemma extends into the muscle cells to form tubular structures called transverse or T-tubules. Each side of the T-tubules consists of a membrane-bound structure called the sarcoplasmic reticulum,...
    Feedback Regulation of Calcium Concentration01:27

    Feedback Regulation of Calcium Concentration

    Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
    Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
    Excitation-Contraction Coupling in Skeletal Muscles01:20

    Excitation-Contraction Coupling in Skeletal Muscles

    Excitation-contraction coupling is a series of events that occur between generating an action potential and initiating a muscle contraction. It occurs at the triad, a structure found in skeletal muscle fibers that comprise a T-tubule and terminal cisternae of the sarcoplasmic reticulum on each side. These triads are visible in longitudinally sectioned muscle fibers. They are typically located at the A-I junction — the junction between the A and I bands of the sarcomere.
    When an action potential...
    Relaxation of Skeletal Muscles01:29

    Relaxation of Skeletal Muscles

    The period of muscle contraction primarily influences the duration of stimulation at the neuromuscular junction (NMJ), the presence of free calcium ions in the sarcoplasm, and the availability of energy or ATP to support contractions.
    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 Contraction01:25

    Smooth Muscle Contraction

    Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
    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...