Kinetics of glutamate-induced cell death in primary cortical cells. Cortical cells isolated from 19 day old fetal rat brains were cultured for 7 days and treated with 5 mM glutamate for the indicated times in a neurobasal medium containing 2% antioxidant free B27. LDH release (% maximum) was measured after 3,6,8 and 24 h of treatment. Data are the mean ± SEM values from at least 3 experiments. *P < 0.05 compared with control ** P < 0.05 compared to 3,6,8 h control.