Biochemical parameters of pregnant rats and their offspring exposed to different doses of inorganic mercury in drinking water

This work investigated the effects of low and high doses of inorganic mercury in drinking water on biochemical parameters of pregnant rats and their offspring. Female Wistar rats were treated during pregnancy with 0, 0.2, 0.5, 10 or 50 μg Hg2+/mL as HgCl2. Rats were euthanized on day 20 of pregnancy. Pregnant rats presented a decrease in total water intake in all doses of mercury tested. At high doses, a decrease in the total food intake and in body weight gain was observed. Pregnant rats exposed to 50 μg Hg2+/mL presented an increase in kidney relative weight. Mercury exposure did not change serum urea and creatinine levels in any of the doses tested. Moreover, mercury exposure did not change porphobilinogen synthase activity of kidney, liver and placenta from pregnant rats in any of the doses tested, whereas fetuses of pregnant rats exposed to 50 μg Hg2+/mL presented an increase in the hepatic porphobilinogen synthase activity. In general, pregnant rats presented alterations due to HgCl2 exposure in drinking water. However, only the dose 50 μg Hg2+/mL appeared to be enough to cross the blood-placenta barrier, since at this dose the fetuses presented change in the porphobilinogen synthase activity.