[Auto-oxidation test for the determination of lipid peroxidation capacity of liver tissue homogenates of young and old mice].

The activity of superoxide dismutase (SOD) and the lipid-peroxidation capacity, i.e., the autoxidation of lipids during incubation at 37 degrees C for 3 h under aerobic conditions was measured in liver tissue homogenates of young (1.5-month-old) and old (24-month-old) inbred female Balb/c mice. The lipid peroxidation capacity was found to be significantly higher in young mice than in old ones. The pretreatment of young mice with allopurinol, a specific inhibitor of xanthine oxidase, remarkably decreased the lipid peroxidation capacity without any modification of SOD activity. SOD levels were equal in young and old mice. Our results suggest that the lipid peroxidation capacity of liver tissue depends, not only on the level of polyunsaturated fatty acids, but, in general, also on the state of a finely regulated counterbalance of pro- and antioxidant factors. The autoxidation test seems to be a suitable in vitro method for measuring the lipid peroxidation capacity of liver tissue.