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Updated: Jun 4, 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

Atrial cardiomyocyte calcium signalling.

Martin D Bootman1, Ioannis Smyrnias, Rüdiger Thul

  • 1Laboratory of Molecular Signalling, The Babraham Institute, Babraham, Cambridge, CB22 3AT, UK. martin.bootman@bbsrc.ac.uk

Biochimica Et Biophysica Acta
|February 8, 2011
PubMed
Summary

Calcium (Ca2+) signals in atrial cells are less understood than in ventricular cells, impacting heart function and leading to conditions like atrial fibrillation. Unlike ventricular cells, atrial cells lack T-tubules, affecting Ca2+ signal propagation and contraction.

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06:22

Isolation of High Quality Murine Atrial and Ventricular Myocytes for Simultaneous Measurements of Ca2+ Transients and L-Type Calcium Current

Published on: November 3, 2020

Area of Science:

  • Cardiology
  • Cell Physiology
  • Calcium Signaling

Background:

  • Calcium (Ca2+) signaling is crucial for cardiomyocyte function, yet atrial cell Ca2+ dynamics remain less characterized than ventricular cells.
  • Atrial cardiomyocytes contribute significantly to cardiac output, and their dysfunction is linked to atrial fibrillation.
  • A key structural difference, the absence of transverse tubules (T-tubules) in atrial myocytes, dictates distinct Ca2+ handling compared to ventricular myocytes.

Purpose of the Study:

  • To elucidate the unique patterns of Ca2+ signaling in atrial cardiomyocytes.
  • To understand how structural differences, specifically the lack of T-tubules, influence Ca2+ propagation and atrial myocyte contraction.
  • To investigate the mechanisms underlying enhanced atrial contraction in response to inotropic stimulation.

Main Methods:

  • Electrophysiological recordings to assess Ca2+ transients.
  • Confocal microscopy to visualize Ca2+ signal propagation.
  • Pharmacological manipulation using agonists like isoproterenol.

Main Results:

  • In the absence of T-tubules, electrical excitation in atrial myocytes initiates peripheral Ca2+ signals.
  • Under resting conditions, these peripheral signals do not fully engage the contractile machinery, resulting in modest contraction.
  • Stimulation with isoproterenol triggers a global, centripetal Ca2+ wave, enhancing contraction and contributing to improved blood pumping.

Conclusions:

  • The lack of T-tubules in atrial myocytes leads to spatially distinct Ca2+ signaling patterns.
  • Peripheral Ca2+ signals in atrial cells require specific stimulation to propagate centrally and enhance contraction.
  • Understanding these Ca2+ dynamics is vital for comprehending atrial function and developing treatments for related cardiac conditions.