Related Experiment Videos
Catalase is needed to avoid tissue peroxidation in Rana perezi in normoxia
G Barja de Quiroga1, M López-Torres, R Pérez-Campo
1Department of Animal Biology-II (Animal Physiology), Faculty of Biology, Complutense University, Madrid, Spain.
Abstract:
1. In order to clarify the relative role of catalase (CAT) and glutathione peroxidases (GSH-Px) at normal and high O2 tensions, Rana perezi frogs were chronically treated with aminotriazole (AT), hyperoxia, or both. 2. A 100% survival was observed with both treatments. Hyperoxia increased liver catalase and kidney TBA-RS and decreased GSH-Px. 3. AT caused quantitatively higher alterations than hyperoxia in both organs: CAT was depleted, TBA-RS increased (114% in kidney) and GSH-Px decreased. 4. It is concluded that in Rana perezi (a) CAT, in spite of its much higher KM and Vmax in relation to GSH-Px, is needed to avoid oxidative stress even in normoxia; (b) normoxic tissues have significative amounts of H2O2; (c) GSH-Px does not compensate the lack of CAT.