In vivo production of nitric oxide after administration of cyclohexanone oxime

Cyclohexanone oxime (CHOX), an intermediate used in the synthesis of polyca prolactam (Nylon-6), has been reported to be hematotoxic in Fischer rats. T he in vivo metabolism of CHOX was found to release nitric oxide, which was detected in venous blood by electron paramagnetic resonance spectroscopy as the nitrosylhemoglobin complex. In vitro incubation of CHOX with venous bl ood resulted in the formation of the characteristic nitrosylhemoglobin comp lex, suggesting that the blood was a possible site for metabolism. Excessiv e nitric oxide production may, in part, contribute to the observed toxicity of CHOX.