Is the zinc neuroprotective effect caused by prevention of intracellular zinc accumulation?

Zinc plays an important role in the functioning of all cells, including neurons. The precise mechanisms responsible for its neurotoxic and neuroprotective effects remain unclear despite extensive investigations. Similar Zn(+2) effects can also be observed in cells outside the nervous system, and their lower sensitivity to hypoxia prolongs the cytotoxic effect of excess zinc. The evident dualism of zinc's effects depends primarily on the energetic state of the particular cell and the efficacy of ion pumps; on genetically conditioned mechanisms regulating Zn efflux from cells and Zn sequestration inside the cell; and on the concentration of extracellular free Zn.