Cortical cultures were preconditioned with oxygen–glucose deprivation for 10–30 min as indicated and then exposed to 300 μm NMDA for 5 min, 50 μm kainate (with 10 μm MK801 to block secondary NMDA receptor activation) for 24 hr, or 200 μm glutamate for 5 min. Twenty-four hours later, resultant neuronal death was assessed by LDH release to the bathing medium, scaled to the release associated with near complete neuronal death without glial death (=100, induced by exposure to 300 μm NMDA for 24 hr). Numbers are mean LDH + SE;n = 16 cultures per condition pooled from four experiments. Death after preconditioning in all cases was not different from control (p > 0.05 by one-way ANOVA).