STUDIO DELLA SINTESI DELLA CATALASI EPATICA CON FERRO RADIOATTIVO IN TOPI NORMALI E PORTATORI DI SARCOMA 180

Abstract

The synthesis of hepatic catalase in normal and S.180 bearing mice at different times after tumor implantation was studied by injection of 59Fe and successive isolation of cytoplasm proteins. On the basis of several control experiments the presence of ferro-proteins other than catalase in the isolated material was excluded. In a series of experiments with mice bearing 5 days tumors, the catalasic activity appeared already reduced, the radioactive iron incorporation on the contrary was increased. In a second series, where mice with 10 and 15 days tumors were used, the depression of catalase activity was very evident. The radioactive iron incorporation was proportionally much more reduced, and sometimes almost abolished. It is concluded that the tumor induces first an increase of the rate of destruction, and later a block of the hepatic catalase synthesis.