Uranium modifies or not behavior and antioxidant status in the hippocampus of rats exposed since birth

In view of the known sensitivity of the developing central nervous system to pollutants, we sought to assess the effects of exposure to uranium (U) — a heavy metal naturally present in the environment — on the behavior of young rats and the impact of oxidative stress on their hippocampus. Pups drank U (in the form of uranyl nitrate) at doses of 10 or 40 mg.L^-1 for 10 weeks from birth. Control rats drank mineral water. Locomotor activity in an open field and practice effects on a rotarod device decreased in rats exposed to 10 mg.L^-1 (respectively, -19.4% and -51.4%) or 40 mg.L^-1 (respectively, -19.3% and -55.9%) in compared with control rats. Anxiety (+37%) and depressive-like behavior (-50.8%) were altered by U exposure only at 40 mg.L^-1. Lipid peroxidation (+35%) and protein carbonyl concentration (+137%) increased significantly after exposure to U at 40 mg.L^-1. A significant increase in superoxide dismutase (SOD, +122.5%) and glutathione peroxidase (GPx, +13.6%) activities was also observed in the hippocampus of rats exposed to 40 mg.L^-1. These results demonstrate that exposure to U since birth alters some behaviors and modifies antioxidant status. (author)