[Dynamics of RNA synthesis and transport into the intact and regenerating rat liver in the presence of sublethal doses of actinomycin D]. / Dinamika sinteza i transporta RNK v intaktnoi i regeneriruiushchei pecheni krys na fone deistviia subletal'nykh doz aktinomitsina D.

The time-dependent characteristic of RNA synthesis has been studied against the effect of sublethal doses of actinomycine D in cells with different proliferative activity, connection of synthesized RNA with RNP-particles of nuclei and its transport into the ribosomes and cytoplasmic postribosomal fraction. Against a background of actinomycine D sublethal doses (150 and 300 micrograms per 100 g body weight) from 0.5 to 4% of RNA is synthesized in comparison with the original level. The level of specific radioactivity of RNA depends on the original functional state of the liver. The newly synthesized RNA is found in the nuclei RNP-particles and transported into the cytoplasm. It is localized in ribosomes (2-3% in intact and about 6% in regenerating liver from the original level) and in the postribosomal fraction (8-10% and 16-18% in intact and regenerating liver, respectively. It is supposed that RNA synthesized against the effect of sublethal doses of actinomycine D takes part in conservation and restoration of realization of genetic information system activity, that is observed 12 hours after the antibiotic injection.