[Effect of cortisone on free and bound RNA polymerase levels in rat liver cell nuclei].

Free and template-engaged RNA-polymerase activities were measured in nuclei from control and cortisone-stimulated rat livers. Both types of nuclei contain free and engaged alpha-amanitin sensitive (RNA-polymerase II) and insensitive (RNA-polymerase II) activities. In nuclei isolated after cortisone injection (1.5 and 3 hours) the stimulation of RNA-polymerase I in engaged form is observed. Unlike it, the higher activity of RNA-polymerase II in the free form is observed after cortisone induction, the activity of bound form being unchanged.