You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Inhibition of Cellular Antioxidants: A Possible Mechanism of Toxic Cell Injury
Charles D. Puglia and Saul R. Powell
Environmental Health Perspectives
Vol. 57 (Aug., 1984), pp. 307-311
Published by: The National Institute of Environmental Health Sciences
Stable URL: http://www.jstor.org/stable/3429932
Page Count: 5
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Cells that utilize molecular oxygen generate highly reactive oxygen-derived free radicals. Endogenous cellular oxidants inactivate oxidant free radicals and protect aerobic cells from oxidant injury. Glutathione, glutathione reductase, and superoxide dismutase are key components of this antioxidant defense. Inhibition of antioxidant components would be expected to result in cell injury. Using exposure to oxygen at high pressure to increase the level of oxidant free radicals, evidence is presented to support the hypothesis that inhibition of cellular antioxidants renders organisms more susceptible to oxygen toxicity. Diethyldithiocarbamate at doses of 250, 500 and 1000 mg/kg inhibited rat brain superoxide dismutase activity and shortened onset time to seizures in a dose-related manner in 4 ATA oxygen. Carmustine at doses of 12.5, 25 and 50 mg/kg inhibits glutathione reductase activity in rat brain in proportion to the dose. Time to onset of seizures of rats pretreated with carmustine prior to exposure to 4 ATA oxygen was shortened, and oxidized glutathione levels were increased in the cortex and subcortex. These data suggest that inhibition of antioxidant components results in organisms becoming more sensitive to oxygen toxicity. Compounds that inhibit cellular antioxidants may produce toxic cell injury by permitting intracellular oxidant free radicals to attack essential cell constituents.
Environmental Health Perspectives © 1984 The National Institute of Environmental Health Sciences