[Changes in the self ultraviolet fluorescence of HeLa cells undergoing ionizing irradiation]

A study was made of the influence of irradiation on the ultra-violet fluorescence respond of the resting HeLa cells being in the stationary growth phase. No change in the cell ultra-violet fluorescence (UVF) intensity was seen immediately after irradiation (1.5 hours). The time dynamics observation of fluorescence intensity changes after irradiation demonstrated the highest values of UVF on the 3rd day--at the start proliferating point. At doses of 10 and 500 rad the action of irradiation on HeLa cells has an opposite UVF respond, compared with the control. The effect of the 500 rad dose irradiation increases the cell UVF intensity on the 3rd recultivating day, but the 10 rad dose irradiation makes it lower compared to the control level. Radiometric analysis makes it clear that HeLa cell UVF changes are not related to the change of protein synthesis with the precursors of 3H-tryptophan.