title: Metallothionein, essential elements and lipid peroxidation in mercury-exposed suckling rats pretreated with selenium.
abstract: Detoxification of mercury (Hg) with selenium (Se) in the early postnatal period with regard to the expression of metallothionein protein (MT), essential element status, and lipid peroxidation level in tissues has not been studied. Seven-day-old Wistar pups were orally pretreated with Se [6 μmol Na2SeO3/kg body weight (b.w.)] for 3 days and then cotreated with Hg (6 μmol HgCl2/kg b.w.) for the following 4 days. This group (Se + Hg) was compared to the groups treated with Hg, Se, or vehicle (control). Compared to the Hg-group, Se + Hg-group exhibited lower renal MT expression, reduced accumulation of Hg, Cu and Zn, and reduced excretion of Se, Hg and Zn in urine. In the liver, MT was stimulated by Se treatment in both, Se and Se + Hg-group. Hepatic and brain levels of the endogenous essential elements Cu, Fe, Mg, and Zn remained unchanged in all of the studied groups. Brain Hg levels and oxidation of lipids measured as thiobarbituric acid reactive substances were diminished in Se + Hg-group of pups compared to the Hg-group. This study suggests that Se pretreatment can help reduce Hg in the tissues of suckling rats, simultaneously preventing impairment of essential element levels in the kidneys and their excessive excretion via urine. Also, Se was shown to prevent oxidative damage of lipids in the brain, which is particularly susceptible to Hg during the early postnatal period.
authors.affiliation: Analytical Toxicology and Mineral Metabolism Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000, Zagreb, Croatia.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Orct
authors.forename: Maja
authors.initials: M
authors.lastname: Lazarus
authors.forename: Marija
authors.initials: M
authors.lastname: Ljubojević
authors.forename: Ankica
authors.initials: A
authors.lastname: Sekovanić
authors.forename: Ivan
authors.initials: I
authors.lastname: Sabolić
authors.forename: Maja
authors.initials: M
authors.lastname: Blanuša
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000833:Animals, Suckling; D005260:Female; D007668:Kidney / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D008628:Mercury / Q000008:administration & dosage / Q000378:metabolism* / Q000633:toxicity; D008668:Metallothionein / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012643:Selenium / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D014018:Tissue Distribution
chemical_list: D008668:Metallothionein; D008628:Mercury; D012643:Selenium