Effects of phenobarbital administration on levels of physiological antioxidants in rat liver.

Administration of phenobarbital to rats over a period of 5 days was shown to increase hepatic lipid peroxidation concomitant with induction of cytochrome P-450 and cytochrome c reductase. The purpose of this study was to determine whether the increase in lipid peroxidation was due to a lowering in hepatic antioxidants. The results show that increased lipid peroxidation was not due to a decreased level of antioxidants since the fat-soluble antioxidants were unchanged and ascorbate, a water-soluble antioxidant, was elevated. The relationship of the increase in hepatic ascorbate to enhanced lipid peroxidation is discussed.