[The effect of gamma irradiation on the proliferative activity of the cambial epithelium in a culture of thymus stromal cells].

A study was made of the effect of gamma radiation on proliferation of thymus stroma epithelial cells (EC) of newborn mice (CBA x C57Bl/6)P1 where EC content varied from 55% to 85%. EC proliferation was assessed 24 and 48 h after gamma irradiation by studying the mitotic activity of thymus EC and rate of MTT recovery (which permitted us to determine the nature of proliferating cells by their morphology). The quantitative characteristics of the two methods were identical. The effect of gamma radiation was assessed at various cultivation times. Irradiation at the time of inoculation reduced the proliferation of cells to logarithmic phase of growth. Irradiation with doses of 10 and 20 Gy after two-day cultivation inhibited proliferation of thymus EC and with 15 Gy increased the proliferative activity of thymus epithelium.