Biophysical characterization of inwardly rectifying potassium currents (IK1, IK, ACh, IK,Ca) using sinus rhythm or atrial fibrillation action potential waveforms

Rok, strany: 2015, 383 - 393

Although several physiological, pathophysiological and regulatory properties of IK1, IK, ACh and the small-conductance Ca2⁺ activated K⁺ current IK,Ca have been identified, quantitative biophysical details remain unclear. Both IK1 and IK, ACh are implicated in atrial fibrillation (AF), and recently also IK,Ca has been speculated to be linked with the genesis and sustainability of AF. All these three currents have been shown to be involved in the electrical remodeling in the atria of patients suffering from AF, and it is therefore important to characterize their biophysical properties and compare their relative current contribution in atrial electrophysiology in both sinus rhythm (SR) and AF. The aim of this study is to investigate the contribution of the three potassium currents when subjected to voltage protocols adapted from atrial action potentials recorded in human tissue at 1 and 3 Hz. The current recordings were performed in the HEK-293 heterologous cell system expressing either IK1, IK, ACh or IK,Ca to establish the individual contribution of each of these currents during the voltage changes of atrial action potential waveforms. IK1 primarily contributes to the atrial electrophysiology at the latter part of repolarization and during the diastolic phase, while both IK,Ca under high [Ca2+]i and IK, ACh contribute relatively most during repolarization.

ISO 690:

Tang, C., Skibsbye, L., Yuan, L., Bentzen, B., Jespersen, T. 2015. Biophysical characterization of inwardly rectifying potassium currents (IK1, IK, ACh, IK,Ca) using sinus rhythm or atrial fibrillation action potential waveforms. In General Physiology and Biophysics, vol. 34, no.4, pp. 383-393. 0231-5882.

APA:

Tang, C., Skibsbye, L., Yuan, L., Bentzen, B., Jespersen, T. (2015). Biophysical characterization of inwardly rectifying potassium currents (IK1, IK, ACh, IK,Ca) using sinus rhythm or atrial fibrillation action potential waveforms. General Physiology and Biophysics, 34(4), 383-393. 0231-5882.