Related Experiment Video

Updated: Oct 17, 2026

X-ray Diffraction of Intact Murine Skeletal Muscle as a Tool for Studying the Structural Basis of Muscle Disease
08:26

X-ray Diffraction of Intact Murine Skeletal Muscle as a Tool for Studying the Structural Basis of Muscle Disease

Published on: July 18, 2019

Time-resolved two-dimensional X-ray diffraction study of the effect of shortening on activation of contracting

H Iwamoto1, T Suzuki, T Fujisawa

  • 1Experimental Research Division, SPring-8, JASRI, Hyogo, Japan. iwamoto@spring8.or.jp

Pflugers Archiv : European Journal of Physiology
|April 14, 2000
PubMed

More Related Videos

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles14:02

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles

Published on: November 1, 2012

An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery08:08

An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery

Published on: May 11, 2011

Related Concept Videos

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.
Actin and Myosin in Muscle Contraction01:16

Actin and Myosin in Muscle Contraction

Actin and myosin are contractile proteins that form the sarcomere found in skeletal muscle tissues for regulating muscle contraction. Actin, a globular contractile protein, interacts with myosin for muscle contraction. The skeletal tissue appears striped or striated under a microscope due to the repeated arrangement of contractile proteins actin and myosin along the length of myofibrils. Dark A bands and light I bands repeat along myofibrils, and the alignment of myofibrils in the cell causes...
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.
Muscle Stimulation Frequency01:22

Muscle Stimulation Frequency

The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Motor Unit Stimulation01:20

Motor Unit Stimulation

When the neuron of a motor unit fires an action potential, it triggers a series of events, leading to a twitch contraction in the muscle fibers. The process of excitation-contraction coupling is crucial in relaying the action potential to the muscle fibers.
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...