2-Nitropropane-induced liver DNA and RNA base modifications: differences between Sprague-Dawley rats and New Zealand white rabbits.

2-Nitropropane (2-NP), a hepatocarcinogen in male Sprague-Dawley rats but not, under the same conditions, in male New Zealand White rabbits, induces characteristic base modifications in rat liver DNA and RNA including increases in 8-oxoguanine and the formation of 8-aminoguanine. We compared the levels of these modifications in the two animal species at 6, 18 and 42 h after a single i.p. treatment with 1.12 mmol/kg 2-NP. Significantly less nucleic acid base modifications were found to be produced in rabbit liver than in rat liver. Thus, the relative resistance of the rabbit to the hepatocarcinogenicity of 2-NP correlates with decreased levels of 2-NP-induced liver DNA and RNA base damage.