Oxidative stress responses in different organs of Jenynsia multidentata exposed to endosulfan.

We evaluate antioxidant responses of Jenynsia multidentata experimentally exposed to sublethal concentrations of endosulfan (EDS). The main goal was to determine differences in the response between different organs to assess which one was more severely affected. Thus, we exposed females of J. multidentata to EDS during 24h, measuring the activity of GST, GR, GPx, CAT and LPO in brain, gills, liver, intestine and muscle of both exposed fish and controls. GST activity was inhibited in gills, liver, intestine and muscle of exposed fish but was induced in brain. GR and GPx activities were increased in brain and gills at 0.014 and 0.288 microg L(-1), respectively. GPx activity was inhibited in liver and muscle at all studied concentrations whereas inhibition was observed in the intestine above 0.288 microg L(-1). Exposure to 1.4 microg L(-1) EDS caused CAT inhibition and increase of LPO levels in liver. LPO was also increased in brain at almost all concentrations tested. We find that the brain was the most sensitive organ to oxidative damage. Thus, J. multidentata could be used as a suitable bioindicator of exposure to EDS measuring activities of antioxidant enzymes in brain and liver as biomarkers.