Document Type : Original Article
Medical Physics Department, Medical Sciences Faculty, Tarbiat Modares University, Tehran, Iran
Neuroscience Research Center and Physiology Department, Medical Faculty, Shahid Beheshti University (Medical Campus), Tehran, Iran
Objective: The aim of this study was to investigate the effects of a 217 Hz magnetic field of mobile phone GSM 900 exposure on the bioelectric activity of F1 neuronal cells of the land snail.
Materials and Methods: According to the magnetic field measurement of the mobile phone, a range of flux intensities of magnetic fields (0.46 - 229 μT) at a frequency of 217 Hz was produced by magnetic field coils. The bioelectrical activity of F1 nerve cells at different time intervals was recorded, using intracellular recording under current clamp conditions in control, sham and field exposed groups.
Results: Magnetic field exposure decreased the amplitude of action potential and the firing frequency of F1 nerve cells. Furthermore, it resulted in a significant (p<0.05) increase in the amplitude of after hyperpolarization (AHP) and duration of action potential. Change in the cell’s electrophysiological parameters was associated with a decrease in neuronal excitability. Magnetic field exposure affected also the resting membrane potential of F1 cells in a bimodal fashion, including depolarization and hyperpolarization. Considering the exposure condition, most of the alterations in the electrical activity of F1 nerve cells induced by magnetic fields exposure were reversible.
Conclusion: These findings suggest that 217 Hz magnetic fields of mobile phones with different intensities affect the spontaneous bioelectrical activity of F1 nerve cells and exert inhibitory effects on neuronal excitability. There is evidence for the existence of an amplitude window and these electrophysiological alterations occur within this amplitude window. The reversibility of the magnetic field- induced most electrophysiological alterations in the neuronal behavior under our experimental conditions was observed.