[Physicochemical parameters of rat liver chromatin during nonhormonal induction]

The changes of RNA-polymerase activity of hepatocytes nuclei, chromatin circular dichroism (CD) spectra and differential melting curves of hepatocytes of rats which were injected hydrocortisone or amino acid mixture intraperitoneally have been studied. Actinomycin D reduces essentially RNA-polymerase activity and maximum of CD spectra. Under the influence of hydrocortisone or amino acid mixture the inhibiting action of antibiotic is taken off but the RNA-polymerase activity and maximum of CD spectra don't achieve the meanings found under the influence of inductors only. The antibiotic injection changes essentially the chromatin melting parameters. A conclusion has been drawn that the amino acid mixture and hydrocortisone effect the transcription process affecting the different levels of chromatin structure.