ELF magnetic fields tuned to ion parametric resonance conditions do not affect TEA‐sensitive voltage‐dependent outward K⁺ currents in a human neural cell line

Abstract

Despite the experimental evidence of significant biological effects of extremely low frequency (ELF) magnetic fields (MFs), the underlying mechanisms are still unclear. Among the few mechanisms proposed, of particular interest is the so called "ion parametric resonance (IPR)" hypothesis, frequently referred to as theoretical support for medical applications. We studied the effect of different combinations of static (DC) and alternating (AC) ELF MFs tuned on resonance conditions for potassium (K(+)) on TEA-sensitive voltage-dependent outward K(+) currents in the human neuroblastoma BE(2)C cell line. Currents through the cell membrane were measured by whole-cell patch clamp before, during, and after exposure to MF. No significant changes in K(+) current density were found. This study does not confirm the IPR hypothesis at the level of TEA-sensitive voltage-dependent outward K(+) currents in our experimental conditions. However, this is not a direct disprove of the hypothesis, which should be investigated on other ion channels and at single channel levels also.

Extremely Low Frequency Electromagnetic Fields Facilitate Vesicle Endocytosis by Increasing Presynaptic Calcium Channel Expression at a Central Synapse

“…Despite accumulating experimental evidence suggesting significant biological effects, the underlying mechanisms are poorly understood. Laboratory studies have pointed to the initial effects of ELF-EMF being on the cellular level, especially the physiological properties of the cell membrane and channels 6 7 8 9 10 . Therefore, the neurons in the central nervous system are likely to be the most sensitive candidates, as exposure to ELF-EMF induces electrical fields and currents, which may excite or suppress neuronal activities through interactions with voltage-gated channels 11 12 .…”

Some recommendations for experimental work in magnetobiology, revisited

“…Thus, why would they be useful in magnetobiology? While FCs have indeed been used in magnetobiology studies [GavoS ci et al, 2013;Castello et al, 2014;Usselman et al, 2014], they are, to date, definitely not a standard. Further, theoretical models linking DC fields and the RF range have been proposed, such as the radical pair mechanism [Rodgers and Hore, 2009;Hore and Mouritsen, 2016], or the one by Matronchik and Belyaev [2008] based on a slow non-uniform rotation of charged nucleoids.…”

“…Another issue that is neglected in the majority of studies is the need to physically decouple the coil system from the culture dishes or their support, in order to avoid the effects of coil vibrations [GavoS ci et al, 2013]. When the coils are active, a physical vibration can be produced due to the attraction/repulsion of adjacent wire loops; e.g., for coils fed by an AC current at frequency f a vibration at 2f frequency takes place.…”

“…Hence, there are both experimental and theoretical reasons to pose the question of whether all magnetobiology experiments ought to be carried out in RFshielded cages/facilities. While FCs have indeed been used in magnetobiology studies [GavoS ci et al, 2013;Castello et al, 2014;Usselman et al, 2014], they are, to date, definitely not a standard. It is worth noting that in experiments performed inside incubators, the incubator itself-if electrically grounded, as usualcan work as an FC.…”