[The effect of low doses of ionizing radiation on intracellular pH, ATP content and synthetic activity in cultured Chinese hamster fibroblasts].

X irradiation of Chinese fibroblasts with doses of 0.05-0.15 Gy was shown to cause intracellular pH (pHi) changes: its diminishing during the first 40-60 min by 0.16-0.18 pH units, then the return to the control level 120 min after irradiation and, finally, the increase by 0.18-0.20 pH units. Simultaneously, the synthesizing activity of the cells changed in the same way. The ATP level changed in the opposite way: increased when pH fell and decreased when pH grew. It was shown that pHi changes were connected with the changes in Na+/H(+)-exchange system, and they seemed to be primary in the chain of the alterations observed.