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Isolation, Culture, and Functional Characterization of Adult Mouse Cardiomyoctyes

Isolation, Culture, and Functional Characterization of Adult Mouse Cardiomyoctyes

Published on: September 24, 2013

Myocyte repolarization modulates myocardial function in aging dogs.

Andrea Sorrentino¹, Sergio Signore¹, Khaled Qanud²

¹Departments of Anesthesia and Medicine, and Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts;

American Journal of Physiology. Heart and Circulatory Physiology

|January 24, 2016

Summary

This summary is machine-generated.

Aging hearts show impaired contractile reserve due to prolonged action potential duration in cardiomyocytes. This electrical remodeling compromises function under stress, contributing to age-related heart dysfunction.

Keywords:

aging contractile reserve myocardium

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Last Updated: Mar 26, 2026

Isolation, Culture, and Functional Characterization of Adult Mouse Cardiomyoctyes

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Published on: September 24, 2013

Isolation and Functional Characterization of Human Ventricular Cardiomyocytes from Fresh Surgical Samples

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Analysis of Cardiac Contractile Dysfunction and Ca2+ Transients in Rodent Myocytes

Analysis of Cardiac Contractile Dysfunction and Ca2+ Transients in Rodent Myocytes

Published on: May 25, 2022

Area of Science:

Cardiology
Gerontology
Physiology

Background:

Myocardial aging mechanisms causing ventricular dysfunction are not fully understood.
The aging heart exhibits decreased functional reserve.
Defining age-related cardiac changes is crucial for understanding heart failure.

Purpose of the Study:

To investigate the effects of aging on myocardial and myocyte function in beagle dogs.
To identify structural and functional alterations in the aging heart.
To elucidate the mechanisms behind decreased cardiac performance with age.

Main Methods:

Evaluation of ventricular, myocardial, and myocyte function in dogs aged 3 to 14 years.
Assessment of anatomical and structural properties of the heart and cardiomyocytes.
Analysis of electrical properties, including action potential duration and repolarization.

Main Results:

Aging did not cause ventricular hypertrophy; myocardial composition was modestly affected.
Aged cardiomyocytes exhibited altered electrical and mechanical properties.
Prolonged action potential duration and remodeled repolarization were observed in older dogs.
These myocyte alterations negatively impacted contractile reserve.

Conclusions:

Defects in cardiomyocyte electrical and mechanical properties are key determinants of the senescent cardiac phenotype.
Delayed electrical repolarization in aging cardiomyocytes contributes significantly to age-related heart muscle disease (myopathy).
Compromised contractile reserve renders the aging heart vulnerable to decompensation under stress.