Transplantation system for determining the clonogenic survival of parenchymal hepatocytes exposed to ionizing...

An in vivo transplantation technique has been developed which can be utilized to determine the reproductive survival of parenchymal hepatocytes exposed either in vitro or in vivo to both physical and chemical genotoxic agents. We have used this assay system to determine the survival of liver cells exposed to sparsely ionizing radiation. The D0 value of the survival curve was 249 rads and the extrapolation number was 1.2. These results indicate that hepatocytes irradiated while in the G0 phase are unable to accumulate sublethal damage to an appreciable extent if they are stimulated to undergo replication within 24 hr after the infliction of the damage.