N-nitrosodialkylamines do not function as substrates for liver monoamine oxidase.

Since reports in the literature [Rowland, I.R., Lake, B. G. & Gangolli, S. D. (1980) Mutat. Res. 72, 63-72] have implicated hepatic monoamine oxidase (EC 1.4.3.4) in the activation of N-nitrosodialkylamines to mutagens, it is of basic pharmacological and biochemical interest to determine if these compounds could serve as substrates for this enzyme. The dialkylnitrosamines N-nitrosodiethylamine, N-nitrosodimethylamine, and N-nitrosodibenzylamine were tested and found not to be substrates, competitive inhibitors, or irreversible inhibitors of liver monoamine oxidase. Thus, any role for monoamine oxidase participation in the mutagenic activation of these compounds must be subsequent to an initial conversion of these compounds to their respective secondary amines.