[Neutral DNAse activity in rat tissues in radiation carcinogenesis].

The activity of neutral DNAse and its natural protein inhibitor was determined in the liver, brain and spleen of albino rats with malignant tumours of mammary gland and other organs. The tumours appeared 14-20 months after the irradiation of rats with fast neutrons (0.5-1.

[Activity of DNAase I inhibitor in subcellular fractions of rat tissues].

The inhibitory activity in the mitochondrial and postmitochondrial fractions of the liver, spleen and thymus of albino rats was studied with respect to pancreatic DNase I. It is shown to be due to the presence of thermolabile substances of protein nature (natural inhibitors of DNase I) in the subcellular fractions of the organs under study. A higher inhibitory activity is detected in the postmitochondrial fraction of all the tissues under investigation.