Inhibition of endothelial cell conditioned medium (EC-CM) induced pro-apoptotic molecule expression by isoflurane. To examine the effect of pretreated isoflurane on neuronal cell survival and death under culture with EC-CM, we performed western blot analysis using Bcl-2 and Bax. (B) The Bcl-2 protein was significantly upregulated in neuronal cells incubated with EC-CM of isoflurane, RAP, or isoflurane RAP treated groups in the tPA and OGD/R condition. (C) In contrast to Bcl-2, the protein levels of Bax was significantly downregulated in neuronal cells incubated with EC-CM of isoflurane, RAP or isoflurane + RAP-treated groups in the tPA and OGD/R condition. (E) Bcl-2 protein levels were significantly increased in neuronal cells incubated with EC-CM of isoflurane, MG-132, or isoflurane + MG-132-treated groups in the tPA and OGD/R condition. (F) Bax was significantly decreased in neuronal cells incubated with EC-CM of isoflurane, MG-132 and isoflurane + MG-132-treated groups in the tPA and OGD/R condition. *p< 0.05, **p< 0.01, ***p< 0.001 vs. OGD/R + tPA group, the one-way ANOVA (means ± SEM, OD of Bcl-2 and Bax(n=3))