AGE-DEPENDENT DIFFERENT INFLUENCE OF CARBON-TETRACHLORIDE ON BIOTRANSFORMATION OF XENOBIOTICS, GLUTATHIONE CONTENT, LIPID-PEROXIDATION AND HISTOPATHOLOGY OF RAT-LIVER

15- and 60-day-old male rats were treated with different doses of CCl4 orally. 24 h later cytochrome P-450 (P450) concentration, 7-ethoxyres orufin 0-deethylation (EROD) and 7-pentoxyresorufin O-deethylation (PE ROD) activities were determined. Whereas P450 and EROD are lowered to the same extent in both ages, PEROD shows a more pronounced inhibition in the livers of younger rats. The formation of endogenous lipid pero xides (measured as thiobarbituric acid reactive substances) is drastic ally increased only in the livers of young rats. The hepatic glutathio ne (GSH) content was unaffected by CCl4 treatment whereas oxidized glu tathione is more increased in the livers of adult rats. This can be ca used by a higher activity of GSH-peroxidase in the livers of adult rat s. The changes in NADPH-induced lipid peroxidation and chemiluminescen ce correlate partially with the changes in P450 and biotransformation reactions. Histopathologically the liver damage is more extensive in s uckling rats. The necrosis is localized predominantly in the perivenou s tissue, which has normally the highest activities of toxification an d detoxification enzymes.