[Activation of membrane lipid peroxidation in the liver of young and old rats by thyroxine and actinomycin D].

Thyroxine and actinomycin D evoke activation of enzymatic peroxide oxidation of membrane lipids in the liver mitochondria and microsomes 24 hours after their separate or combined administration to Wistar males rats. In young animals the thyroxine effect is less pronounced than in old ones. Activation of peroxidation of membrane lipids with thyroxine or actinomycin D is not additive. Thyroxine had no essential influence on the glutathione-S-transferase activity of mitochondrial and postmitochondrial fractions of liver homogenates which is higher in old animals.