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Updated: May 8, 2026
09:32
Methods for the Isolation, Culture, and Functional Characterization of Sinoatrial Node Myocytes from Adult Mice
Published on: October 23, 2016
Hyperpolarization-activated current, If, in mathematical models of rabbit sinoatrial node pacemaker cells
Arie O Verkerk1, Ronald Wilders
1Department of Anatomy, Embryology and Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Biomed Research International
|August 13, 2013
Summary
The hyperpolarization-activated current, If, plays a key role in heart pacemaker cells. This study reviews If models and proposes a new one based on experimental data to clarify its function in heart rate control.
Area of Science:
- Cardiology
- Computational Biology
- Electrophysiology
Background:
- Sinoatrial (SA) node pacemaker cells exhibit a hyperpolarization-activated ionic current, If.
- The precise role of If, also known as the funny or pacemaker current, in SA nodal cell activity is debated.
Purpose of the Study:
- To review mathematical models of If used in computer simulations.
- To compare these models with experimental data.
- To propose a novel, experimentally-validated model for If.
Main Methods:
- Review of existing mathematical descriptions of the If current.
- Comparison of simulation models with experimental data from SA node cells.
- Development of a new If model.
Main Results:
- Existing mathematical models for If show significant differences.
- These models exhibit discrepancies when compared to experimental findings.
- A novel If model is proposed, better aligning with experimental observations.
Conclusions:
- The role of If in cardiac pacemaking requires accurate modeling.
- Discrepancies between current models and experimental data highlight the need for refinement.
- The proposed novel model offers a more accurate representation of If for future simulations.
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