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Updated: Jun 5, 2026
08:34
Isolation of Atrial Myocytes from Adult Mice
Published on: July 25, 2019
Cardiac myocyte interconnections at gap junctions Role in normal and abnormal electrical conduction.
J E Saffitz1, R H Hoyt, R A Luke
1Departments of Pathology, Medicine, and Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA.
Trends in Cardiovascular Medicine
|January 18, 2011
Summary
Structural changes in heart muscle cells and their gap junctions after myocardial infarction disrupt electrical coupling, leading to dangerous ventricular arrhythmias. Understanding these changes is key to preventing reentrant tachycardias.
Area of Science:
- Cardiovascular Physiology
- Cardiac Electrophysiology
- Myocardial Infarction Research
Background:
- Reentrant ventricular tachycardias in healed myocardial infarcts are linked to altered myocyte intercellular coupling.
- Gap junctions between myocytes are critical for electrical signal propagation in the heart.
Purpose of the Study:
- To investigate the structural determinants of anisotropic current spread in normal myocardium.
- To understand how alterations in myocyte structure and gap junctions contribute to arrhythmogenesis after myocardial infarction.
Main Methods:
- Correlative morphometric and electrophysiologic studies were performed.
- Analysis focused on myocyte shape, packing, and gap junction characteristics.
Main Results:
- Myocyte shape, packing, and gap junction distribution significantly influence anisotropic current spread.
- Structural alterations in these features are implicated in the electrophysiologic derangements causing reentrant arrhythmias.
Conclusions:
- Intercellular coupling at gap junctions is crucial for preventing ventricular arrhythmias post-myocardial infarction.
- Multiple gap junction proteins offer new insights into regulating cardiac electrical current transfer.
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