Effects of vitamin A on the metabolism and mutagenicity of 2AAF in vitro and on the covalent binding to rat liver DNA/RNA in vivo.

Vitamin A has been shown to affect the in vitro metabolism of 2AAF. At low concentrations of retinol or retinyl palmitate, a decreased production of ring-hydroxylated as well as deacetylated and N-hydroxylated metabolites was observed, measured by high performance liquid chromatography. The increased mutagenicity of 2AAF observed after addition of vitamin A in the Ames test cannot therefore be explained as a result of stimulated N-hydroxylation. However, the addition of retinol was found to enhance the mutagenicity of the metabolite N-OH-2AAF in the presence of an S-9 fraction of rat liver homogenate. No differences with regard to the covalent binding of 2AAF or its metabolites to rat liver DNA/RNA in vivo could be demonstrated in animals fed diets with normal or high vitamin A content.