Modification of production of reactive oxygen species in mouse peritoneal neutrophils on exposure to low-intensity modulated millimeter wave radiation

The effect of low-intensity modulated electromagnetic radiation of extremely high frequencies (EHF EMR) on the production of reactive oxygen species by mouse peritoneal neutrophils was investigated. The neutrophil activity in synergistic reaction of calcium ionophore A23187 and phorbol ester PMA was estimated by luminol-dependent chemiluminescence technique. The cells were irradiated for 20 min in the far-field zone of the channel radiator in the presence of A23187 and then were activated by PMA. It was shown, that continuous EHF EMR(SO mu W cm(-2)) inhibited quasi-resonantly the synergistic reaction. The maximum effect was about 25% at carrier frequency of 41.95 GHz. The effect had S-like dependence on an absorbed energy flux density, and in a range from 20 to 150 mu W cm(-2) varied slightly and on the average was about 24%. The modulated radiation with carrier frequency of 41.95 GHz and modulation frequency of 1 Hz activated the synergistic reaction, but at modulation frequencies of 0.1, 16 and 50 Hz inhibited one. At fixed modulation frequency of 1 Hz the nonlinear dependence of the effect on the carrier frequency was found. The synergistic reaction was activated in the frequency range of 41.95-42.05 GHz and was inhibited at the frequencies of 41.8-41.9 GHz. The effect was observed only at high A23187 concentrations used. The obtained results prove the opportunity of control over neutrophil functioning by low-intensity modulated EHF EMR, presumably manipulating by coupled systems of enzyme reactions. (C) 1998 Elsevier Science S.A. All rights reserved.