Caspase inhibitors on zinc neurotoxicity.A, LDH release (n = 4; mean + SEM) 16 hr after 15 min zinc exposure done in the absence (Zinc) or presence of 100 μm zVAD-fmk (+VAD) or zDEVD-fmk (+DEVD).B, LDH release (n = 3; mean + SEM) after 20 hr exposure to 25 μm zinc in the absence or presence of 100 μm zVAD-fmk (100 μm), zDEVD-fmk (100 μm), or 50 μm zYVAD-fmk.Asterisks denote difference from respective zinc exposure alone (p < 0.05; two-tailedt test).