Effects of chronic inhalation of ethylene oxide on lipid peroxidation and glutathione redox cycle in rat liver.

The chronic effects of ethylene oxide (EO) on hepatic metabolism were investigated. Both reduced and oxidized forms of glutathione in liver were not changed during chronic exposure to EO for 13 weeks. On the other hand, increased levels of malondialdehyde were detected at 6 weeks and at the end of exposure periods, as compared with those of control livers. The activity of glutathione reductase was decreased at 6 and 13 weeks and therefore in inverse proportion to the lipid peroxide, although the reduced form of glutathione did not decrease probably due to the increase of de novo synthesis. These results indicate that EO treatment enhances lipid peroxidation and also affects glutathione redox cycle, but glutathione did not play a causative role in the induction of lipid peroxidation under the present conditions.