Rapid oxidative stress induced by N-nitrosamines

We have investigated the generation of prooxidant state shortly after administration of N-nitrosamines (NA) to rats. N-Nitrosodimethylamine (NDMA) was found to increase ethane exhalation (EE) rapidly in a dose-related manner. EE remained elevated for several days after single doses of NDMA. Similarly, lipid peroxidation (LP) in the liver (measured by four methods) increased rapidly showing a peak 20 min after NDMA dose. The increase of LP was preceded by a decrease in retinol concentration in the liver. N-Nitrosodiethanolamine, too, increased EE and LP in the liver, whereas N-nitrosomethylbenzylamine had no effect. Thus, hepatocarcinogenic NA induced LP in their target tissue, and the LP enhancing effects of NA were not related to their acute toxic effects.