[Induction of double-strand DNA breaks in rat bone marrow cells by X-radiation]

The method of sedimentation in a neutral sucrose gradient was used to study double-stranded DNA in a total population of rat bone marrow cells. As a result of cell lysis in neutral conditions the fragments of double--stranded DNA were formed having the molecular mass of (3 +/- 0.3) X 10(9)D. A study was made of the dynamics of accumulation of DNA double-strand breaks after irradiation of a cell suspension. It was shown that the yield of double-strand breaks and the ratio between single- and double--strand breaks in bone marrow cells were similar to those of cultured L5178Y cells.