Effects of 60 Hz magnetic field exposure on polymorphonuclear leukocyte activation.
We have investigated the effects of a sinusoidal 60 Hz magnetic field on free radical (superoxide anion) production, degranulation (beta-glucuronidase and lysozyme release) and viability in human neutrophils (PMNs). Experiments were performed blindly in very controlled conditions to examine the effects of a magnetic field in resting PMNs and in PMNs stimulated with a tumor promoter: phorbol 12-myristate 13-acetate (PMA). Exposure of unstimulated human PMNs to a 60 Hz magnetic field did not affect the functions examined. In contrast, exposure of PMNs to a 22 milliTesla (mT), 60 Hz magnetic field induced significant increases in superoxide anion (O2-) production (26.5%) and in beta-glucuronidase release (53%) when the cells were incubated with a suboptimal stimulating dose of PMA. Release of lysozyme and lactate dehydrogenase was unchanged by the magnetic field, whether the cells were stimulated or not. A 60 Hz magnetic field did not have any effect on O2- generation by a cell-free system xanthine/xanthine oxidase, suggesting that a magnetic field could upregulate common cellular events (signal transduction) leading to O2- generation and beta-glucuronidase release. In conclusion, exposure of PMNs to a 22 mT, 60 Hz magnetic field potentiates the effect of PMA on O2- generation and beta-glucuronidase release. This effect could be the result of an alteration in the intracellular signaling.
Khadir
R
R
Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-0111, USA.
Morgan
J L
JL
Murray
J J
JJ
D000328:Adult; D017209:Apoptosis; D015550:Cell Degranulation; D002474:Cell-Free System; D005966:Glucuronidase / Q000378:metabolism; D006801:Humans; D008163:Luminescent Measurements; D008280:Magnetics; D018375:Neutrophil Activation; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects*; D013481:Superoxides / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D013481:Superoxides; D005966:Glucuronidase; D013755:Tetradecanoylphorbol Acetate