Metallothioneins (MTs) are metal-binding proteins that are expressed in many tissues including brain. MTs protect cells and organs against metal toxicity and oxidants. Among MTs, a brain-predominant subtype MT-III has prominent neuroprotective activity against various types of damage. Here we show that the expression of MT-III is induced in cultured normal human astrocytes by hypoxia, and that overexpressed MT-III protects human embryonic kidney cells from hypoxia, suggesting that MT-III can protect the brain from hypoxic damage.