Profile of nonprotein thiols, lipid peroxidation and δ-aminolevulinate dehydratase activity in mouse kidney and liver in response to acute exposure to mercuric chloride and sodium selenite

The effects of mercury (Hg2+) and selenite (Se4+) on delta-aminolevulinic acid dehydratase (delta-ALA-D) activity, 2-thiobarbituric acid reactive substances (TBARS) and nonprotein sulfhydryl content (NPSH) in mouse kidney and liver were investigated. Male mice were given a single i.p. injection of Hg2+ and/or Se4+ (25 mumol/kg) and were killed at 6, 12, 24 and 48 h after treatment. Hg2+ inhibited renal delta-ALA-D at 6 and 12 h after treatment. Se4+ abolished the inhibitory effect of mercury on renal delta4-ALA-D at 12 h after treatment. Renal and hepatic NPSH content decreased after Hg2+ exposure and selenite inhibited, at least in part, the Hg-induced oxidation of renal and hepatic NPSH. Se4+ and Hg2+ when injected alone, did not alter hepatic or renal TBARS levels; however, simultaneous exposure to these compounds increased hepatic and renal TBARS levels at 12 and 48 h after treatment, respectively. Present results suggest that selenium abolishes the interaction of Hg2+ with sulfhydryl groups of protein and nonprotein sources. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.