The effect of melaxen and valdoxan on the activity of the glutathione antioxidant system in rats with experimental hyperthyroidism

Abstract

The activity of the glutathione system and conjugated diene content (CD) have been investigated in the liver and blood serum of rats with experimental hyperthyroidism treated with melaxen and valdoxan. The study of glutathione reductase (GR), glutathione peroxidase (GP) and glutathione transferase (GST) activities increased under this pathology has shown that administration of these compounds decreased these activities towards control levels. Melaxen and valdoxan administration increased reduced glutathione (GSH) content as compared with untreated hyperthyroid rats. This increase may be associated with its decreased utilization for detoxification of toxic products of free radical oxidation (FRO). Administration of the melatonin correcting drugs also tended to normalize the CD level increased in the liver and blood serum of hyperthyroid rats. Results of this study indicate that melaxen and valdoxan exhibit positive effect on free radical homeostasis. This appears to be accompanied by a decrease in the load of the glutathione antioxidant system in comparison with the examined pathology.