The effects of mercuric chloride and sodium selenite on glutathione and total nonprotein sulfhydryls in the kidney of the black bullhead (Ictalurus melas)

1. Mercuric chloride injections (10 μmol/kg) caused renal nonprotein sulfhydryls (NPSH) to decrease within 3 hr and then increase by 72 hr after injection.2. Selenium injections (10 μmol/kg) caused renal NPSH increases.3. The Se-promoted increases in renal NPSH more than compensated for the Hg-induced decreases when the two elements were simultaneously injected.4. This Se-promoted increase in renal NPSH may explain why Se promotes renal uptake of Hg when the two elements are simultaneously injected.5. Glutathione accounted for most (77–95%) of the NPSH.