Reparative processes of damaged chromosomes in non-stimulated human peripheral blood lymphocytes by the fractionated irradiation method and temperature variation]

The fractionation experiments were carried out on resting lymphocytes. Non-stimulated lymphocytes were X-irradiated at the total dose of 200 r separated into two equal parts by either 5-hour or 20-hour intervals. The whole blood samples were kept during the intervals between the exposure at the temperature of 20degrees C or 37degrees C. All the cultures were made after the last radiation exposure at 37degrees C. Dicentrics and centric rings were scored. It is shown that a fractionation effect takes place in resting lymlf-dose at 37degrees C and is absent at the temperature of 20degrees C. It is suggested that there is the repair in lymphocytes at the stage Go, at least, from the dose of 100 r.