Different responses of cytosolic and mitochondrial glutathione in rat livers after ethylene oxide exposure.

Acute effects of ethylene oxide (EO) at the concentration of 500 and 1500 ppm on glutathione and glutathione reductase of the cytosol and mitochondria in rat liver were examined. The levels of reduced glutathione content and the glutathione reductase activity in the cytosol at 1500 ppm exposure decreased to approximately 10% and 60% of those of control rats, respectively. The decreases in glutathione content and glutathione reductase activity in the mitochondria were less significant than those in the cytosol. Both mitochondrial NADPH-cytochrome c reductase and cytochrome c oxidase activities were only slightly affected by these EO exposures. These results indicate that the change in glutathione content in the cytosol mainly occurred due to the response to EO exposure, and that the mitochondrial glutathione did not serve for such cellular function.