The early temporal responses of mouse liver and kidney catalase (EC 126.96.36.199, H2O2:H2O2 oxidoreductase) were examined following i.p. administration of heterologous protein and glycoproteins, bacterial endotoxin, bradykinin, allylisopropylacetylcarbamide, talcum, 3-amino-1,2,4-triazole, and Ehrlich ascites tumor and fluid extracts. With the exception of Ehrlich ascites tumor, all substances examined showed depression of mouse liver catalase activity 0.5 to 3 hr after administration, although not as pronounced as that of 3-amino-1,2,4-triazole. Nucleotides added to purified human hepatic catalase, mouse liver, and human erythocyte catalases resulted in the inhibition of catalatic activity. AMP and its related di- and triphosphate nucleotide esters appeared to be most effective in the inhibition of catalatic activity. Coenzymes I and II both reduced catalatic activity, and the oxidized forms and UMP esters also demonstrated inhibition of catalatic activity. The inhibition of catalatic activity by these nucleotides was immediate and reversible. With the exception of glutathione and reduced forms of coenzymes I and II, the nucleotides had no effect on peroxidatic activity. It is suggested that inhibition of catalatic activity may be mediated in part by nucleotides during normal and abnormal metabolic processes in the liver.
This work was supported in part by USPHS Research Grant R01 CA 10671-04 from the NIH.