Effect of selenium on the toxicity of methylmercury on nervous tissue in culture

Abstract

Effects of sodium selenate and selenite on the toxic effect of methylmercuric chloride (MMC) on nervous tissue in culture were studied. Sliced newborn rat cerebella were cultured in a medium containing MMC and selenate or selenite. The concentrations of sodium selenate and selenite that showed remarkable protective effect against the neurotoxicity of MMC were 0.8 and 0.2 × 10 −5 m, respectively. The protective effect of sodium selenite was additive with that of dl-α-tocopherol acetate (vitamin E). However, 4 × 10 −5 m sodium selenate and 1 × 10 −5 m sodium selenite per se showed an obvious toxic effect on the outgrowth of nerve fibers and cells from cerebellum tissue in culture. The toxicity of selenium was additive to that of MMC. These results indicate that oxidized selenium at low concentrations is able to modify the neurotoxicity of MMC and that different states of selenium produce different degrees of protection. They suggest further that the adverse effect of selenium is additive to the toxicity of alkyl mercurial at the toxic level of selenium.