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 extremel y high frequencies (EHF EMR) on the production of reactive oxygen species b y 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 cont inuous EHF EMR(SO mu W cm(-2)) inhibited quasi-resonantly the synergistic r eaction. 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 wa s about 24%. The modulated radiation with carrier frequency of 41.95 GHz an d modulation frequency of 1 Hz activated the synergistic reaction, but at m odulation frequencies of 0.1, 16 and 50 Hz inhibited one. At fixed modulati on frequency of 1 Hz the nonlinear dependence of the effect on the carrier frequency was found. The synergistic reaction was activated in the frequenc y 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 function ing by low-intensity modulated EHF EMR, presumably manipulating by coupled systems of enzyme reactions. (C) 1998 Elsevier Science S.A. All rights rese rved.