Cell Survival and Radiation Damage in Growth Cartilage

Abstract

The development of recovery clones in radiation injured growth cartilage is described and the significance of later degeneration of clones is related to the cell-survival system based on clone counting. Radiation survival curves for cartilage plate cells was drawn from data on 94 animals and interpreted in terms of the equation surviving fraction S = ne-D/Do where n = extrapolation number and Do = slope. Data for cartilage plate cells in rat tibiae are: animals breathing air, Do [image] 165 rads, n [image] 6; anoxia, Do [image] 340 rads, n [image] 20; animals breathing O2 at 3 atmospheres, Do [image] 145 rads; O2 at 1 atm., Do [image] 150 rads; 95% O2 and 5% CO2, Do [image] 150 rads. Variation in recovery ratio with interval between 2 fractionated doses is described. Results are compared with survival data from other mammalian cell systems.