title: No effects of intermittent 50 Hz EMF on cytoplasmic free calcium and on the mitochondrial membrane potential in human diploid fibroblasts.
abstract: The recently described increase in DNA strand breaks of cultured human diploid fibroblasts after intermittent exposure to extremely-low-frequency electromagnetic fields (ELF-EMF) of more than about 70 microT ELF-EMF is difficult to explain by a direct induction of covalent bond disruption. Therefore the hypothesis has been tested that ELF-EMF-induced DNA strand breaks might be mediated by cellular processes that cause alteration of the intracellular concentration of free calcium ([Ca2+]i) and/or the membrane potential (DeltaPsi(m)). [Ca2+]i was determined by the ratiometric fura-2 technique. Changes in DeltaPsi(m) were assessed by using the potential-dependent lipophilic cationic probe JC-1. Human fibroblasts were exposed to intermittent ELF-EMF (50 Hz, 1000 microT). Although exposure of fiboblasts to ELF-EMF resulted in a highly significant increase in DNA strand breaks as determined by the comet assay, no effect on JC-1 fluorescence emission or on [Ca2+]i has been observed when comparing exposed with sham-exposed cells. Therefore, it is suggested that ELF-EMF-induced DNA strand breaks are unlikely to be caused by intracellular changes that affect [Ca2+]i and/or DeltaPsi(m).
authors.affiliation: Division of Occupational Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria. alex.pilger@akh-wien.ac.at
authors.forename: Alexander
authors.initials: A
authors.lastname: Pilger
authors.forename: Sabine
authors.initials: S
authors.lastname: Ivancsits
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Diem
authors.forename: Melanie
authors.initials: M
authors.lastname: Steffens
authors.forename: Hans-Albert
authors.initials: HA
authors.lastname: Kolb
authors.forename: Hugo W
authors.initials: HW
authors.lastname: Rüdiger
mesh_terms: D002118:Calcium / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism*; D004171:Diploidy; D004307:Dose-Response Relationship, Radiation; D004560:Electricity; D004574:Electromagnetic Fields; D005347:Fibroblasts / Q000502:physiology* / Q000528:radiation effects*; D006801:Humans; D008564:Membrane Potentials / Q000502:physiology / Q000528:radiation effects*; D008928:Mitochondria / Q000502:physiology / Q000528:radiation effects*; D011829:Radiation Dosage
chemical_list: D002118:Calcium