Objective To evaluate the effect of isoflurane post-conditioningon the expression of pro apoptotic proteins in the conical neurons exposed to oxygen-glucose deprivation and restoration (OGD/R) in rats.Methods Primary cortical neurons isolated from male Sprague-Dawley rats (within 24h after birth),were cultured in vitro and inoculated in 6-well culture plate (2 ml/well) at a density of 1 × 106/ml.The cells were divided into 3 groups (n =12 each) using a random number table:control group(group C),OGD/R group,and isoflurane post-conditioning group (Ⅰ group).In OGD/R group,the cells were incubated in glucose-free BBS aerated with 95 ％ N2 for 30 min followed by restoration of 2-glucose supply for 1 h.At 24 h of incubation,the cells were collected for detection of neuronal apoptosis (.using Hoechst/PI staining),caspase-3 expression (by Western blot),expression of Bid,Bim and Puma mRNA (by PCR),and expression of Bid,Bim and Puma (by Western blot).Apoptosis rate was calculated.Results Compared with S group,the apoptosis rate was significantly increased,and the expression of caspase-3 and Bid,Bim and Puma mRNA and protein was upregulated in OGD/R group.The apoptosis rate and expression of caspase-3 and Bid,Bim and Puma mRNA and protein were significantly lower in Ⅰ group than in OGD/R group.Conclusion Isofluranepost-conditioning inhibits apoptosis in the cortical neurons exposed to OGD/R through down-regulating pm-apoptotic proteins in rats.