Related Experiment Video

Updated: Sep 30, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
10:53

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Published on: July 3, 2013

Biphasic effect of a gradual rise in plasma calcium concentration on vulnerability to fibrillation

L Bertrix, J Lang, M Lakhal

    Naunyn-Schmiedeberg'S Archives of Pharmacology
    |April 1, 1985
    PubMed

    More Related Videos

    Contractions of Human-iPSC-derived Cardiomyocyte Syncytia Measured with a Ca-sensitive Fluorescent Dye in Temperature-controlled 384-well Plates07:42

    Contractions of Human-iPSC-derived Cardiomyocyte Syncytia Measured with a Ca-sensitive Fluorescent Dye in Temperature-controlled 384-well Plates

    Published on: October 18, 2018

    Imaging Calcium Dynamics in Subpopulations of Mouse Pancreatic Islet Cells08:03

    Imaging Calcium Dynamics in Subpopulations of Mouse Pancreatic Islet Cells

    Published on: November 26, 2019

    Related Concept Videos

    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...
    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.
    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...
    Disturbances in Heart Rhythm01:29

    Disturbances in Heart Rhythm

    Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
    Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
    Cardiac Action Potential01:30

    Cardiac Action Potential

    Cardiac action potentials are essential for proper heart function, enabling the rhythmic contractions needed for adequate blood circulation. Nodal cells and Purkinje fibers, specialized for electrical conduction, generate these action potentials.
    The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
    Ionic Basis of Cardiac Action Potentials
    Dysrhythmias III: Characteristics of Dysrhythmias01:29

    Dysrhythmias III: Characteristics of Dysrhythmias

    Dysrhythmias, also known as arrhythmias, are irregular heart rhythms that result from abnormal electrical activity in the heart, affecting its ability to circulate blood efficiently. Tachyarrhythmias, a subset of dysrhythmias, are characterized by abnormally fast heart rates exceeding 100 beats per minute. Here are some types of tachyarrhythmias with their distinct ECG features:Sinus Tachycardia:Sinus tachycardia presents a regular heart rhythm with an increased rate of 101-180 beats per minute.