[The effect of low doses of ionizing radiation on the DNA in the spleen in the irradiation of mice].

The research of low dose gamma-irradiation 137Cs effect on mice line F1 has been carried out under two different intensities: 0.6 cGy per day (dose range 0.6-9.6 cGy) and 6.0 cGy per day (dose range 6.0-60 cGy). High molecular DNA was isolated from spleen of irradiated and intact mice and analyzed by DNA retention method to nitrocellulose filters under physiological ionic strength. Increase in percentage of DNA retention after mice irradiation by doses of 0.6-5.4 cGy with maximum of 1.2 has been found. In dose range 6.0-24 cGy maximum of DNA retention has been observed at dose of 6.0 cGy. DNA preparation did not contain single-strand breaks. It is supposed that the phenomena of increase in percentage of DNA retention is the result of its compactization during the process of adaptive cell response to low dose ionizing radiation exposure.