EFFECTS OF MATERNAL DIETARY SUPPLEMENTATION WITH SELENITE ON THE POSTNATAL-DEVELOPMENT OF RAT OFFSPRING EXPOSED TO METHYL MERCURY IN-UTERO

Female Sprague-Dawley rats were fed a control standard diet or a selen ite (Se) supplemented diet (1.3 p.p.m. Se) for 8 weeks before mating a nd during gestation and lactation. Blood glutathione peroxidase activi ty (GSH-Px) was measured as a biomarker of Se in dames. After mating, the females from two dietary groups were divided into three subgroups (6 groups with 10 animals in each) given 0 (vehicle), 2 or 6 mg/kg met hyl mercury (MeHg) by gavage on days 6-9 of gestation. Day 2 post part urition all litters were standardized to 6 pups per litter and remaini ng pups were used for determination of blood and brain total Hg conten ts. Behavioural testing was performed at two months of age. The result s of the study showed that supplementing the diet with Se partly antag onized some adverse effects of the MeHg such as hypoactivity especiall y in the high MeHg dose group. There were no changes in physical devel opment or body weight except a tendency to decreased body weight in of fspring of mothers exposed to 6 mg Hg/kg. The GSH-Px activity was sign ificantly increased in animals fed on Se supplemented diet. The dietar y Se supplementation resulted in considerably increased concentrations of mercury in the blood of the offspring despite milder signs of CNS toxicity and no increase in brain concentrations of mercury.