Effect of fractionated doses of ionizing radiation on the reproductive function of mouse bone marrow

The experiments were carried out in 159 CPB-S mice, males, aged 10 - 12 weeks. The donor mice received the following doses of X-radiation: one doses of 0 C/kg, 2.58 x 10-2 C/kg, 5.16 x 10-2 C/kg, 10.32 x 10-2 C/kg, and fractionated doses - 2 x 1.29 x 10-2 C/kg, 2 x 2.58 x 10-2 C/kg, 2 x 5.16 x 10-2 C/kg. Each of these fractions was given at the following time intervals: 4, 8, 16, 20, 24 hours. The recipient mice received a dose of 21.93 x 10-2 C/kg. Bone marrow was transplanted in 0.5 ml volumes of suspension containing 106 cells. The recipient mice were killed 9 days after transplantation and after fixation of the spleen the number of colonies was counted. The results of the experiment were subjected to statistical analysis by means of variance analysis and Duncan's test. It was found that there were statistically significant differences between the number of colonies in the spleen of the recipients after one lethal radiation dose, and the number of colonies in the spleen of recipients irradiated with fractionated doses from the interval of 20 hours between the fractions. (author)