MILLIMETER WAVES AT 25 MW CM(2) HAVE NO EFFECT ON HYDROXYL RADICAL-DEPENDENT LIPID-PEROXIDATION/

The effect of millimeter waves on (OH)-O-.-dependent lipid peroxidatio n was studied. Liposomes treated with (OH)-O-.-generating systems such as ferrous sulfate plus hydrogen peroxide and EDTA-Fe3+ plus ascorbic acid showed a marked increase in the amount of lipid peroxides. When these systems were exposed to continuous millimeter waves of 53.6 GHz frequency and incident power density of 25 mW/cm(2), no difference in the formation of lipid peroxides was observed between irradiated and u nirradiated samples. Preirradiation of liposomes with millimeter waves at this frequency and intensity followed by (OH)-O-.-dependent lipid peroxidation did not exhibit any difference in the concentration of li pid peroxides between preirradiated and unirradiated samples. The pres ent results indicate that reported beneficial effects of millimeter wa ves in reducing the toxic effect of chemotherapy do not result from th e direct inhibition of (OH)-O-.-dependent lipid peroxidation.