Effect of Total-body X-irradiation and of Chemical Protector AET Administration on the Activity of Nuclear RNA-polymerase in Regenerating Rat Liver

Nuclear RNA-polymerase activity has been measured in regenerating liver of rats which received before hepatectomy either an injection of AET or a whole-body x-irradiation of 1000 R or a combination of both treatments. AET injection, 1 hour before hepatectomy, delays the increase in enzyme activity still more than does irradiation. No protective effect of AET is observed in rats treated 1 hour before partial hepatectomy, probably because of the higher toxicity of AET to hepatectomized rats. A protective action is, however, detected when AET and irradiation are given 12 hours before partial hepatectomy.