THE ROLE OF NITRIC OXIDE UNDER THE INFLUENCE OF UV-B RADIATION ON YEAST CELLS

. The present work is devoted to the study of nitric oxide production in yeast cells after exposure to UV-B radiation. In addition, a comparative evaluation of the production of reactive oxygen species (ROS) was carried out. The change in the level of ROS was determined using the fluorescent dye 2',7'-dichlorodihydrofluorescein diacetate-H2DCF•DA. That dye is used to determine the level of ROS in living cells. We determined the intracellular concentration of nitric oxide using a fluorescent dye; -4-amino-5-methylamino-2',7'-difluorescein diacetate (DAF-FM). It was found that under the action of UV-B radiation on cells, depending on the dose, the rate of oxidation of the dye 2',7'-dichlorodihydrofluorescein diacetate (H2DCF•DA) increases and a high intensity of DCF fluorescence is observed. Under the action of a high dose (4,8∙102 erg/mm2.) of UV-B rays, the generation of ROS and nitric oxide decreases. As can be seen on the obtained data, at high doses of radiation, the intensity of chemiluminescence of lucigenin remains at a high level.