A morphological study of continuously irradiated lymphosarcoma cells

Mouse lymphosarcoma LS/BL cells, cultivated as a free suspension in the peritoneal cavity of C57Bl mice, were continuously irradiated by 60Co unit at an exposure rate of 35.8 x 10(-5) mC kg-1 s-1 (5 R/h). After 250 and 350 weeks of irradiation these cells were examined in light and electron microscope. Both the cytoplasm and the nucleus underwent morphological alterations under continuous exposure. Areas of advanced cytoplasmic degradation were often observed and many nuclei showed wide indentations and prolongation of their shape. The number of mitochondria and vacuoles in the cytoplasm was increased markedly in the irradiated cells. The authors consider some of the described alterations caused by continuous irradiation to act as compensatory mechanisms of the impaired cell.