CELLULAR-RESISTANCE TO METHYLMERCURY

The destructive pathologic and biochemical consequences of methyl merc ury have been extensively described. Relatively little is known, howev er, about the defensive mechanisms neurons employ to protect themselve s against mercurial injury. Studies using a variety of cell types have disclosed several inducible biochemical responses to heavy metal and pro-oxidant insult These responses include modulation of cellular leve ls of glutathione, metallothionein, hemoxygenase, and other stress pro teins. With few exceptions, however, neurons appear to be markedly def icient in these responses. This suggests the possibility that the phen omenon of selective vulnerability of cells in the nervous system to me rcury and other heavy metals may arise from a critical absence of inhe rent protective mechanisms. Transfection of neural cells with the anti -apoptotic gene, bcl-2, confers partial resistance to a variety of neu rotoxins, including methyl mercury. This approach to providing neuropr otection may represent an efficacious strategy for combating tenacious neurotoxins such as methyl mercury. 1996 Intox Press, Inc.