[The effect of repeated small doses of radiation on cell killing and repair capacity in plateau phase C3H 10T 1/2 cells].
Using plateau phase C3H 10 T 1/2 cells, we studied the effect of multiple-dose irradiation on the repair capacity of cells after further irradiation. Cells were irradiated with repeated doses of 2.5 Gy delivered two fractions per day at 6 to 7 hours interval. The cell survival after exposure to 1 to 9 fractions was lower above fractions as compared to that predicted by calculating from single dose survival curve by assuming that cells retain their capacity to repair radiation damage after each fraction. Repair kinetics experiments showed that cells were less able to repair only slow type potentially lethal damage after test dose following multiple dose irradiations. Thus, it would appear that an enhancement of the lethal expression of potentially lethal damage of three types of damage may, at least in part, contribute to the difference between the cell survival curve after multiple fractions and that predicted by calculation.
Kubota
N
N
Dept. of Radiology, Yokohama City Univ. School Med.
Kakei
M
M
Matusi
K
K
D000818:Animals; D002453:Cell Cycle; D002455:Cell Division / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects*; D002478:Cells, Cultured; D005434:Flow Cytometry; D005720:Gamma Rays; D016014:Linear Models; D051379:Mice; D008809:Mice, Inbred C3H