Fig. 4.

MK-801, an NMDA receptor antagonist, attenuates neuronal damage produced by OGD: representative experiment. Pseudocolor images of PI fluorescence in cultures exposed to OGD (left column) and to OGD combined with MK-801 (30 μm;right column) at the indicated times. The panels at thebottom illustrate the maximum achievable PI fluorescence (after a further 24 hr incubation at 4°C) used to normalize the previous measurements from the same slice. MK-801 pretreatment (15 min before the insult) improved neuronal survival (see Fig. 3).Color scale indicates the relationship between color and fluorescence intensity, with purple andred representing low and high intensities, respectively. Scale bar, 1 mm.