The relationship between oxidative metabolism and lipid peroxidation in rat liver microsomes

7-ethoxycoumarin was not found to induce lipid peroxidation in rat liver microsomes, although it was reported to cause lipid peroxidation in rat cultured hepatocytes. The productions of thiobarbituric acid reactive substances (TBARS) and chemiluminescence (CL) in the presence of some drugs including tolbutamide, naproxen and salicylic acid and their oxidation activities were determined. There was a negative correlation between extent of oxidative stress and oxidation activities. These results suggested that the oxidative metabolism of these drugs did not directly contribute to the microsomal peroxidation reaction. In addition, naproxen-induced microsomal lipid peroxidation was found to occur in rat, but did not in guinea pig.