Effects of caspase inhibitors on glutamate-induced cell death in primary cortical cells. Cortical cells isolated from 19 day old fetal rat brains were cultured for 7 days. Cell death was measured by LDH release assay 6 h after incubation with 1 mM glutamate with or without 30 min pretreatment with 100 μM caspase-3 specific inhibitor z-DEVD or a pan-caspase inhibitor z-VAD (A,B,C and D). Inhibitors alone (E and F) or DMSO (G) had not effect on LDH release. Data are the mean ± SEM for 3 experiments performed. a = P < 0.05 compared with control, b = P < 0.05 compared with glutamate alone.