Activity of some enzymes involved in the metabolism of polyamines in the liver of streptozotocin-diabetic rats.

The effect of diabetes on some enzymes of polyamine metabolism was studied in male rats 1-12 days after administration of streptozotocin. Hepatic ornithine decarboxylase activity decreased in the first days after the administration, but increased thereafter. The decrease was not due to an alteration of the ODC-antizyme concentration, nor to a posttranslational modification catalyzed by transglutaminase. S-adenosylmethionine decarboxylase and ornithine transaminase were both increased. Spermidine acetyltransferase activity was practically unchanged, while its inactivating factor was markedly decreased.