Persistent increase in the rates of apoptosis and dicentric chromosomes in surviving V79 cells after X-irradiation.
In parallel to delayed reproductive death and delayed micronuclei in surviving V79 cells that have been reported, the frequency of apoptosis and dicentrics was investigated in the same cell line, 1-2 weeks after X-ray doses between 1 and 12 Gy. Apoptosis was assessed by morphological criteria after staining with Giemsa and using the Apoptag method in parallel. The frequency of apoptosis peaked 48 h after irradiation at about 35% as a function of dose and then decreased to about 10% on day 3. It remained 10 times higher than in unirradiated cells until day 14. The frequency of dicentric chromosomes 24 h after irradiation increased according to a linear-quadratic function, up to about 110% after 12 Gy, decreased 3 days later to about 10% and remained about 5-fold higher than in control cells. The dose-response relationship was similar for all the various end-points of expression of radiation induced genomic instability, showing a steep increase of the frequency with dose up to 3-4 Gy and with no further increase at higher radiation doses.
Jamali
M
M
Department of Radiation Biology, St Bartholomew's School of Medicine, Queen Mary & Westfield College, London, UK.
Trott
K R
KR
D000818:Animals; D017209:Apoptosis; D002455:Cell Division; D002478:Cells, Cultured / Q000528:radiation effects; D002869:Chromosome Aberrations; D048629:Micronuclei, Chromosome-Defective; D015162:Micronucleus Tests; D011829:Radiation Dosage