[Influence of beta-radiation on human erythrocyte surface potential under eicosanoid metabolism inhibition]. / Vliianie beta-izlucheniia na poverkhnostnyi potentsial éritrotsitov cheloveka pri ingibirovanii metabolizma éikozanoidov.

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.

[Effect of ultra-low dose of ionizing radiation on the surface potential of erythrocytes]. / Vliianie ioniziruiushchego izlucheniia v sverkhmaloi doze na poverkhnostnyi potentsial éritrotsitov.

Effect of ionizing radiation in ultralow dose (5 microGy) on responses of erythrocyte electrophoretic motility (EPM) as a result of adrenoreceptor ligands binding (0.01-100 microM) has been investigated. The opposite directional EPM responses to agonists (adrenaline, isoprenaline) and antagonist (propranolol) of beta-adrenoreceptors was shown. At that, EPM response to the radiation coincides both with the direction and value of acting the beta-adrenoreceptor agonists depressing EPM. The EPM response to a combined action of beta-adrenoreceptors antagonist, propranolol (10 microM), and ionizing radiation is additive. The above listed is capable to evidence about the essential role of adrenoreceptors at formation of erythrocyte membrane surface charge under action of ionizing radiation in ultralow doses.