[Detection of cells resistant to the cytotoxic action of CCl4 in the hepatocyte populations of rats following a single exposure to 4-dimethylaminoazobenzene combined with subsequent injections of the tumor promoter phenobarbital].

It is found that hepatic cells of intact rats measuring 129-192 mcm2 are resistant to cytotoxical action of carbon tetrachloride (CCl4). After a single interperitoneal injection of the carcinogen 4-dimethylaminoazobenzene, small hepatocytes (64-128 mcm2) appear to be maintained for one month following five injections of phenobarbital. These small hepatocytes are resistant to cytotoxical action of CCl4. The resistance was studied using a cytochemical test on succinate dehydrogenase. A direct dependence exists between the cell size and the sensitivity to CCl4 among large sized hepatocytes.