Mutagenicity of N-nitroso pyridinol carbamate with the Salmonella/mammalian microsome test

A genotoxicological study of the new local anaesthetic carbamate derivatives carbisocaine, heptacaine and pentacaine

The potential mutagenic activity of three carbamate derivatives with local anaesthetic activity was investigated. Genotoxic activity was observed after application of Carbisocaine on Euglena gracilis, whereas no activity was detected by Carbisocaine, Heptacaine and Pentacaine on Salmonella typhimurium, Escherichia coli and Drosophila melanogaster.

Analysis of the genotoxic activity of four N-nitroso compounds by the Drosophila mosaic test

Mutagenic activity of 4 nitroso compounds of environmental importance - N-nitroso-morpholine, dinitrosopiperazine, N,N'-dinitroso-pyridinol-carbamate and N-methyl-N-nitroso-p-toluenesulfonamide - was tested by the Drosophila mosaic test. Larvae were fed with the nitroso-compound-containing food for 2-4 days, and when they had developed into adults, their wings were screened for mosaic spots. All 4 compounds were positive. This finding supports the conclusion that the mosaic test - besides other test procedures - may become a tool for identifying mutagens.

Formation of nitroso compounds and mutagens from cinnarizine, ethambutol, piromidic acid, pyridinol carbamate and tiaramide by drug/nitrite interaction

The formation of nitroso compounds and mutagens from 5 nitrogen-containing drugs (cinnarizine, ethambutol, piromidic acid, pyridinol carbamate and tiaramide) by drug/nitrite interaction was examined. On the reaction of 50 micrometers drug and 500 micrometers nitrite at pH 3.0--3.4 and 37 degrees C for 4 h, the considerable formation of nitroso compounds was observed for ethambutol, cinnarizine and pyridinol carbamate. The reaction product of pyridinol carbamate and nitrite was remarkably mutagenic to Salmonella typhimurium TA100 in the absence of S-9 mix. Under conditions presumed to resemble those in the stomach after ingestion of a therapeutic dose of the drug, the formation of nitroso compounds was observed for ethambutol and significant mutagenicity was detected in the reaction product of pyridinol carbamate.