Effect of anti-inflammatory drugs on the activity of antioxidant enzymes and in vivo peroxidation products in the liver and kidney of rat.

1. Four groups of rats were injected with four different anti-inflammatory drugs (indomethacin, phenylbutazone, acetylsalicylic acid and hydrocortisone) and the activities of superoxide dismutase, catalase and glutathione peroxidase were studied in the liver and kidney. 2. The drugs treatment resulted in decreased activity of the enzymes in both organs compared to the control animals. 3. In vivo tissue peroxidation was also effected by the drugs used. 4. Our results indicate that the changes of oxygen free-radical metabolism contribute to the action of these drugs in vivo.