The ryanodine receptors (RyR2s) and L-type calcium channels (LTCC) are known to be important regulators of cardiomyocyte calcium handling and spontaneous calcium release events (SCaEs). However, the influence of their distribution on the behavior of SCaEs is unknown. In our most recent manuscript, recently accepted for publication in the special research topic on ‘Recent Advances in Understanding the Basic Mechanisms of Atrial Fibrillation Using Novel Computational Approaches‘ from Front Physiol, we extended our previous spatial calcium-handling model of the human atrial cardiomyocyte to simulate heterogeneous distributions of RyR2 channels and LTCC (in axial tubules) and identified an increased SCaE incidence for larger heterogeneity in RyR expression. We also incorporated experimental RyR2 distribution from rabbit atrial cardiomyocyte and previously published LTCC distribution to create a final model that accommodates these subcellular structures.

Reference: Sutanto H, van Sloun B, Schönleitner P, van Zandvoort MAMJ, Antoons G, Heijman J (2018) The Subcellular Distribution of Ryanodine Receptors and L-type Ca²⁺ Channels Modulates Ca²⁺-transient Properties and Spontaneous Ca²⁺-release Events in Atrial Cardiomyocytes. Front Physiol, Manuscript accepted on July 23, 2018