Effects of diethylhydroxylamine on hepatic microsomal lipid peroxidation and glutathione S‐transferases

The effects of diethylhydroxylamine (DEHA), a potent free‐radical scavenger, on lipid peroxidation of rat liver microsomes were investigated in vitro. DEHA strongly inhibited ascorbate‐dependent nonenzymatic microsomal lipid peroxidation. DEHA also completely inhibited nonenzymatic lipid peroxidation of heat‐denatured microsomes, indicating that inhibition is protein‐independent. DEHA only moderately inhibited NADPH‐dependent enzymatic microsomal lipid peroxidation. DEHA has been shown to exhibit antitumorogenic properties. However, it had no significant effect on hepatic glutathione S‐transferase, selenium‐independent glutathione peroxidase, or selenium‐dependent glutathione peroxidase activity in the DEHA‐treated CD‐I (ICR) Br male mouse. This suggests that the mode of action of DEHA as an antitumorogenic agent may be different from that of butylated hydroxyanisole, whose antitumor function is attributed to induction of glutathione S‐transferase activity.