Deoxyribonucleoprotein changes and intranuclear DNA and RNA synthesis in rat liver after irradiation and partial hepatectomy

No substantial radiation effect on the polydeoxyribonucleotin level could be detected in the liver of non-operated animals, however, the content and concentration of DNP decreased on the second day after irradiation. The reduced 3H-thymidine incorporation is probably caused by the supression of repair and the disturbance of the last phase of DNA replication. As a consequence of partial hepatectomy the level of polydeoxyribonucleotins increased 6 hours after irradiation. Irradiation of operated animals caused a supression of the DNA synthesis, especially at the twenty fourth hour. The preoperation DNP content was reached on the third day. Irradiation caused a decrease of the DNA concentration in nuclei, the partial hepatectomy itself resulted in increased incorporation of 3H-thymidine up to the twenty fourth hour. After sole irradiation only a moderate, statistically insignificant decrease of the RNA concentration was observed. In the regenerating liver the course of changes in irradiated animals was similar to that in control group animals. (author)