Incorporation of labeled 2,4,5,2',4',5'-hexachlorobiphenyl into the nuclear fraction of rat hepatocytes in vivo.

2,4,5,2',4',5'-[14C] Hexachlorobiphenyl (2,4,5-HCB) a slowly metabolized PCB was given to rats by gastric incubation. The hepatocyte nuclei (HCN) were then isolated and treated with specific hydrolytic enzymes in order to separate the nucleic macromolecules, protein RNA and DNA. The results show that 2,4,5-HCB binds in vivo to hepatocyte nuclei. Liver nuclear proteins bind 70% of 2,4,5-HCB and 30% is found in the DNA fraction. No radioactivity was found in the nuclear RNA fraction at this experimental time (16 h).