RADIOSENSITIVITY OF DIFFERENT AGED HUMAN-LYMPHOCYTES FOLLOWING ELECTRON-IRRADIATION IN-VITRO

Cytochalasin B-blocking micronucleus test and chromosomal aberration a nalysis were used in this study to estimate the yield of individual va riability in radiation response of different aged human lymphocytes. B oth analyses were performed in three groups of adults, aged 18-65 year s, on two sampling times, following irradiation by therapeutical dose of 2 Gy e- in vitro. No statistically significant difference in the in duced yield of exchange aberrations between individuals under consider ation was found. The yield of total aberration data showed greater var iability and was statistically significant in the oldest group against two other adult groups. Regarding to fixation times no statistically significant differences in the induced yield of chromosomal aberration s (exchanges as well as total aberrations) were observed. The study ha s shown a slight increase in spontaneously occurring micronuclei with age. Almost equal mean number of radiation induced micronuclei was obs erved in the groups of adults aged 18-20 and 45-55 years. The highest mean number was observed in the oldest group. Evident variation in num ber of radiation induced micronuclei among individuals from the same a ge group was observed. The results of micronuclei assay for all indivi duals under consideration show statistically significant difference in the yield of radiation-induced micronuclei regarding the second fixat ion time. This study has shown that cytochalasin-B blocking micronucle us test is more sensitive assay than chromosomal aberration analysis f or the estimation of individual radiosensitivity.