Cardiac KATP Channel Modulation by 16Hz Magnetic Fields - a Theoretical Study

Introduction: The exposure to 16Hz magnetic fields (MFs) was shown to be cardio-protective for diseased hearts; still, the mechanism of this effect is unknown. We hypothesize that a possible mechanism is an increased KATP channel open probability due to modulation of the degree of association between K+ ions, having a resonance frequency of 16Hz, and the channel selectivity filter.
Methods: The Fan-Makielski Markovian KATP channel model was adopted, and the MF bio-effect was manifested by lowering the open state energy level, and changing the selectivity filter rate constant α. The model was integrated in a ventricular single cell model and the MF effect on the calcium transients [Ca2+] was assessed.
Results: Periodic pacing (CL=1sec) was applied and a 16Hz or 32Hz MF was turned on at t=0 for 10min. MF exposure gradually decreased [Ca2+] due to KATP channel opening, more strongly at 16Hz , showing a great similarity to experimental data.
Conclusions: 16Hz MF exposure increases the KATP channel open probability, thereby lowering the cellular calcium load. Our model could be integrated in a tissue model to predict optimal MF parameters for future cardiac therapeutic devices.