Related Experiment Video

Updated: Jul 25, 2025

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

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Emerging Evidence for cAMP-calcium Cross Talk in Heart Atrial Nanodomains Where IP3-Evoked Calcium Release Stimulates

Rebecca-Ann B Burton1, Derek A Terrar1

  • 1Department of Pharmacology, University of Oxford, Oxford, UK.

Contact (Thousand Oaks (Ventura County, Calif.))
|June 27, 2023
PubMed

Insights

Calcium signaling via inositol trisphosphate receptors (IP3Rs) in atrial cells contributes to arrhythmias. Crosstalk between calcium and cAMP pathways in atrial myocytes offers new therapeutic targets for treating atrial fibrillation.

Area of Science:

  • Cardiology
  • Molecular Physiology
  • Biochemistry

Background:

  • Atrial arrhythmias, such as atrial fibrillation, pose significant health risks.
  • Understanding calcium handling in atrial myocytes is crucial for addressing these conditions.
  • Inositol trisphosphate (IP3) plays a key role in calcium signaling within the heart.

Purpose of the Study:

  • To elucidate the mechanisms of calcium signaling in atrial myocytes.
  • To investigate the interaction between calcium and cAMP pathways in the atria.
  • To identify potential therapeutic targets for atrial arrhythmias.

Main Methods:

  • Investigated the role of IP3 receptors (IP3Rs) in atrial calcium transients.
  • Examined the function of calcium-dependent adenylyl cyclases (AC8 and AC1) in atrial myocytes.
  • Studied the spatial relationship between IP3Rs and adenylyl cyclases.

Main Results:

  • IP3Rs on sarcoplasmic reticulum augment atrial calcium transients, potentially leading to arrhythmogenesis.
  • IP3-evoked calcium release stimulates adenylyl cyclases AC8 and AC1.
  • AC8 co-localizes with IP3Rs, and AC1 is nearby, indicating localized signaling.

Conclusions:

  • Crosstalk between calcium and cyclic AMP (cAMP) pathways occurs in atrial nanodomains.
  • Similar mechanisms are observed in the sinoatrial node.
  • These findings suggest novel targets for treating atrial arrhythmias.

Keywords:
IP3IP3Radenylyl cyclaseatriacAMPcalciumnanodomains

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