RESUMO
The aim of the research consisted in the study of influence of beta-radiation on response of erythrocyte surface potential to inhibitors of eicosanoid metabolism enzymes (cyclo-, lipoxygenase and phospholipase A2). It was shown, that inhibitors of phospholipase A2 (quinacrine, 10-100 microM), cyclooxygenase (aspirin, 10-100 microM) and cyclo- and lipoxygenase (BW755c, 1-100 microM) lowered electrophoretic mobility (EPM) of erythrocytes by 20-30%. An analogous effect can be exerted by beta-radiation. Nonradioactive leucine in the studied concentrations cannot simulate EPM erythrocytes. Response of cellular EPM to these inhibitors depended on their concentration in the incubation medium. Addition of 14C to the incubation medium changed response of EPM of cells to inhibitors of cyclo- and lipoxygenase but not to quinacrine. However beta-radiation fully abolished the stimulative action of nonspecific activator of phospholipase A2 (Ca-independent), H2O2, on cellular EPM. Under these conditions beta-radiation enhanced EPM response to aspirin only at concentration of 100 microM. The EPM response to BW755c is reduced by irradiation at all concentrations with the exception of equal-effective one (10 microM). Data obtained evidence for modification of eicosanoid metabolism by beta-radiation, probably, as a result of phospholipase A2 inhibition, as evident from elimination by radiation of stimulated action of hydrogen peroxide on EPM. The radiation action can also affect the cyclooxygenase lipoxygenase activity ratio, this activity being mediated by cellular membrane signaling systems.
