Temperature and the Formation of Radiation-induced Chromosome Aberrations. II. The Temperature Dependence of Lesion Repair and Lesion Interaction

Summary

Dicentric chromosome aberration yields have been measured after single-exposure and split-dose irradiations of human lymphocytes with 150 kV X-rays. Various temperature programmes between 4 and 37°C were applied before, during and after irradiations and in the radiation-free interval. It was found that chromatin lesion repair was completely suppressed at 21°C and below, whereas lesionformation is reduced only below 17°C. The interaction between repairable lesions which leads to exchange-type aberrations is also suppressed by low temperatures. Hypothermic suppression of chromatin lesion repair and interaction is fully reversible at least up to 12 h of maintenance of the ‘stored’ state of these lesions.

• chromosome aberration
• temperature
• split dose
• repair
• human lymphocytes