Related Experiment Video
Updated: Mar 2, 2026
08:10
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
2.2K
Connexin Remodeling Contributes to Atrial Fibrillation
Michelle M Jennings1, J Kevin Donahue1
1Case Western Reserve University School of Medicine, MetroHealth Campus.
Journal of Atrial Fibrillation
|May 13, 2017
Summary
Atrial fibrillation involves changes in gap junction proteins, connexins 40 and 43. This remodeling creates electrical instability, promoting sustained reentry and atrial fibrillation.
Area of Science:
- Cardiology
- Electrophysiology
- Molecular Biology
Background:
- Atrial fibrillation (AF) is a major cause of stroke, heart failure, and myocardial infarction.
- Gap junctional remodeling, particularly involving connexins 40 and 43, is crucial in AF development and maintenance.
- Altered connexin expression and localization create a substrate for sustained reentry in AF.
Purpose of the Study:
- To review the mechanisms of atrial fibrillation (AF) related to connexin remodeling.
- To discuss the role of connexins 40 and 43 in AF pathogenesis.
- To explore connexin remodeling as a potential therapeutic target for AF.
Main Methods:
- Literature review of studies investigating atrial fibrillation mechanisms.
- Analysis of research on connexin expression and localization in AF.
- Synthesis of information on the role of gap junctions in cardiac electrical activity.
Main Results:
- Connexin 40 and 43 undergo significant alterations in atrial fibrillation.
- These connexin changes promote an environment conducive to sustained reentry.
- The reentrant substrate is key for AF initiation and maintenance.
Conclusions:
- Connexin remodeling is a fundamental mechanism underlying atrial fibrillation.
- Targeting connexin alterations may offer novel therapeutic strategies for AF.
- Further research into connexin function in AF is warranted.
Related Concept Videos
01:28Mechanism of Cardiac Arrhythmias
2.4K
Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.
2.4K
01:17Intracellular Signaling Affects Focal Adhesions
3.7K
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
Some...
3.7K
01:37Gap Junctions
57.7K
Multicellular organisms employ a variety of ways for cells to communicate with each other. Gap junctions are specialized proteins that form pores between neighboring cells in animals, connecting the cytoplasm between the two, and allowing for the exchange of molecules and ions. They are found in a wide range of invertebrate and vertebrate species, mediate numerous functions including cell differentiation and development, and are associated with numerous human diseases, including cardiac and...
57.7K
01:27Gap Junctions
10.0K
The cytoplasm of adjacent animal cells can exchange small molecules, ions, and secondary messengers via the communication channels which form the gap junctions. These junctions comprise a few hundred to thousands of molecular channels, each made of two halves, called the connexon hemichannel. A connexon is a hexamer of six transmembrane connexin proteins, which assemble radially, thus forming a pore or channel in the center. One connexon hemichannel docks with a corresponding connexon on the...
10.0K
01:19Electrophysiology of Normal Cardiac Rhythm
9.9K
The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase...
9.9K
01:17Pathophysiology of Heart Failure
4.2K
Heart failure (HF) is a progressive syndrome involving ventricles that leads to inadequate cardiac output. It can be classified based on location and output or ejection fraction. Ejection fraction (EF) is an essential measurement in the diagnosis and surveillance of HF. Reduced EF corresponds to systolic heart failure (HFrEF). However, HF with preserved ejection fraction (HFpEF) is becoming increasingly prevalent. Also known as diastolic HF, this form of HF is related to aging. The...
4.2K