[Changes in the nuclear proteinase activity of the liver in gamma-irradiated rats].

Activity of nuclear proteinases in rat liver was studied, by their capacity of splitting a casein substrate, 5-48 h following gamma irradiation. The proteinase activity of nuclei was shown to increase by more than two times in 2-5 h and to decrease by 3-4 times after 15-48 h compared to that of the nonirradiated controls. A sharp decrease in the proteinase activity was also noted in the nuclear matrix of irradiated rat liver.