Comparative study of oxidative stress parameters and acetylcholinesterase activity in the liver of complex frogs.

Comparative activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR), the phase II biotransformation enzyme glutathione-S-transferase (GST), the concentrations of total glutathione (GSH), sulfhydryl groups (-SH) and the activity of the neurotoxicity biomarker acetylcholinesterase (AChE) were investigated in the livers of species belonging to the "complex" (parental species , , and their hybrid kl. ) from the wetland, Obedska bara in Serbia. The condition factor (CF) and hepato somatic index (HSI) were also calculated. All three species were caught at same locality and were exposed to the same environmental conditions. Liver SOD activity was lower in than in kl and ; higher activities of CAT, GR and GST were observed in kl frogs as compared to their parental species. The activity of GSH-Px was significantly lower in kl. The activity of AChE was increased in as compared to kl and . Similar concentrations of GSH and -SH groups were observed in all investigated species. kl had a higher CF, while the HSI was lower when compared to the parental species. Our findings suggest that the parental species ( and ) possess more similar antioxidative responses to environmental conditions than the hybrid species . kl. The obtained results improve our understanding of the biology and physiology of these three closely related species.