N-nitrosodimethylamine, N-nitrosodiethylamine, and N-nitrosomorpholine fail to generate 8-hydroxy-2'-deoxyguanosine in liver DNA of male F344 rats.

The possible oxidative effects of the hepatocarcinogens 2-nitropropane (2-NP), N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA) and N-nitrosomorpholine (NMOR) on nuclear DNA were studied in vivo in male F344 rats. 2-NP and the N-nitrosamines were administered intraperitoneally. In addition, NDEA was given by gavage. DNA was isolated from rat liver and hydrolysed enzymatically. Oxidative DNA damage was determined by measuring 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in a mixture of 2'-deoxyribonucleosides by electrochemical detection. This method allows a detection limit of about 0.1 residue 8-OH-dG per 10(5) 2'-deoxyguanosine (dG). 2-NP drastically increased the content of 8-OH-dG in rat liver by a factor of ca. 12. No elevation above control values could be proved after having dosed the rats with N-nitrosamines.