Abstract |
In studies directed at determining the activities of selected enzymes in lung tissue after in vivo exposure to hyperoxia, 70-day-old rats were exposed to 85% or 90% O2 for 1-14 days. After 7 days of exposure to 90% O2 (1atm), superoxide dismutase activities in mitochondrial and cytosolic fractions increased, respectively, to 245 and 145% of control; glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase activities increased, respectively, to 317, 175, and 413% of control. The levels of reduced glutathione and total nonprotein sulfhydryl compounds were elevated to 195% and 365% of control. Similar changes were observed in rats exposed to 85% O2 for up to 14 days, but to a lesser degree. The changes are interpreted as a reflection of the overall magnitude of oxidant-induced lung injury-reparative processes. The results suggest that hyperoxia induces an increase in lung " antioxidant" defense capabilities. This apparent adaptive response may be important in decreasing the susceptibility of lung tissue to continued O2 toxicity.
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Authors | R E Kimball, K Reddy, T H Peirce, L W Schwartz, M G Mustafa, C E Cross |
Journal | The American journal of physiology
(Am J Physiol)
Vol. 230
Issue 5
Pg. 1425-31
(May 1976)
ISSN: 0002-9513 [Print] United States |
PMID | 1275087
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Sulfhydryl Compounds
- Glucosephosphate Dehydrogenase
- Peroxidases
- Glutathione Peroxidase
- Superoxide Dismutase
- Glutathione Reductase
- Glutathione
- Oxygen
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Topics |
- Animals
- Body Weight
- Bronchi
(ultrastructure)
- Epithelial Cells
- Epithelium
(ultrastructure)
- Glucosephosphate Dehydrogenase
(metabolism)
- Glutathione
(metabolism)
- Glutathione Peroxidase
(metabolism)
- Glutathione Reductase
(metabolism)
- Lung
(enzymology, pathology)
- Male
- Oxygen
(toxicity)
- Peroxidases
(metabolism)
- Rats
- Starvation
- Sulfhydryl Compounds
(metabolism)
- Superoxide Dismutase
(metabolism)
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