Related Experiment Video

Updated: Aug 11, 2026

Contractions of Human-iPSC-derived Cardiomyocyte Syncytia Measured with a Ca-sensitive Fluorescent Dye in Temperature-controlled 384-well Plates
07:42

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

Clinical electrophysiologic effects of tocainide

J L Anderson, J W Mason, R A Winkle

    Circulation
    |April 1, 1978
    PubMed

    More Related Videos

    Electrocardiogram Recordings in Anesthetized Mice using Lead II04:16

    Electrocardiogram Recordings in Anesthetized Mice using Lead II

    Published on: June 20, 2020

    High-Throughput Optical Controlling and Recording Calcium Signal in iPSC-Derived Cardiomyocytes for Toxicity Testing and Phenotypic Drug Screening10:01

    High-Throughput Optical Controlling and Recording Calcium Signal in iPSC-Derived Cardiomyocytes for Toxicity Testing and Phenotypic Drug Screening

    Published on: March 31, 2022

    Related Concept Videos

    Depolarizing Blockers: Mechanism of Action01:28

    Depolarizing Blockers: Mechanism of Action

    Depolarizing blockers act on skeletal muscle fibers' membranes and induce their depolarization. Most depolarizing blockers have two quaternary N+ atoms that bind the nicotinic acetylcholine receptors and cause neuromuscular blockade within minutes.
    Succinylcholine is the most commonly used depolarizing blocker. Chemically, it constitutes two molecules of acetylcholine joined together by an acetate methyl group. They act on the receptors in the same way as acetylcholine. Because succinylcholine...
    Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers01:22

    Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers

    Class I antiarrhythmic drugs are used to treat various types of arrhythmias or irregular heart rhythms. These drugs block the sodium (Na+) channels in the cardiac cells, thereby affecting the movement of electrical impulses across the heart. Class I antiarrhythmic drugs are divided into three subgroups: Class IA, Class IB, and Class IC, each with distinct mechanisms of action and effects on the heart.
    Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...
    Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers01:24

    Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers

    Adrenergic stimulation generally impacts cardiac rate and rhythm. Specifically, stimulation of the β-adrenoceptors triggers an increase in intracellular calcium ion influx and pacemaker currents, which may cause arrhythmias. Catecholamines like adrenaline also demonstrate β2-adrenoceptor-mediated hypokalemia, impacting cardiac action potential and disrupting the normal cardiac rhythm. Class II antiarrhythmic drugs are β-adrenoceptor antagonists or β-blockers, which indirectly block calcium...
    Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers01:12

    Antiarrhythmic Drugs: Class III Agents as Potassium Channel Blockers

    Class III antiarrhythmic drugs are a group of medications that can prolong action potentials in the heart. They achieve this by blocking potassium channels or enhancing inward currents from sodium channels. However, these drugs have a unique property of "reverse use-dependence," which is most pronounced at slower heart rates and can lead to torsades de pointes—a specific type of arrhythmia. However, it is essential to note that excessive QT interval prolongation—a measure of the heart's...
    Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers01:20

    Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers

    Class IV antiarrhythmic drugs, such as verapamil and diltiazem, block calcium channels. They primarily affect the heart, slowing the conduction in calcium-dependent tissues like the SA and AV nodes. These drugs manage reentrant supraventricular tachycardia (SVT) and reduce ventricular rate in atrial flutter/fibrillation.
    Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
    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