Figure 1: Duration--dependent endothelial cell death due to oxygen-glucose deprivation. Cultures of murine brain-derived endothelial cells (b.End. 3) were exposed to varying durations of oxygen-glucose deprivation followed by 24 h reperfusion. Cell death was estimated by trypan blue (a), whereas cell viability was estimated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (b). oxygen-glucose deprivation durations of 4 and 6 h led to dose-dependent cell death (~40% after 4 h, ~90% after 6 h) and cell viability (~20% after 4 h, 5% after 6 h), whereas 2 h oxygen-glucose deprivation had little effect on either. *P < 0.01 versus controls. OGD: Oxygen-glucose deprivation, Con: Controls