Effects of 50 Hz electromagnetic fields on rat cortical synaptosomes

Abstract

Nerve cells are very responsive to weak pulsed electromagnetic fields (EMFs). Such non-ionizing radiation, with frequencies of 0–300 Hz and 0.1–100 mT, can affect several cellular activities, with unusual dose–response characteristics. The present study examined the effect of a 2-h exposure of synaptosomes on a system generating a peak magnetic field of 2 mT. We evaluated the changes of the synaptosomal mitochondrial respiration rate and ATP production, membrane potential, intrasynaptosomal Ca²⁺ concentration, and the release of free iron and F2-isoprostanes. O₂ consumption and ATP production remained unchanged in exposed synaptosomes. The intrasynaptosomal Ca²⁺ concentration decreased slowly and no depolarization of the synaptosomal membrane was detected. Finally, the release of free iron and F2-isoprostanes by synaptosomal suspensions also remained unchanged after EMF exposure. These results indicate that the physiological behavior of cortical synaptosomes was unaffected by weak pulsed EMFs.

Keywords

electromagnetic field F2-isoprostanes free iron release free radicals synaptosomes membrane potential

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