Fig. 4

NMDA exerts a neuroprotective effect similar to that of RIPC in vitro. A Representative brightfield image showing morphologic changes of primary neurons in WT or KO-derived neurons after NMDA pretreatment. Scale bar = 50 μm. B Quantification of surviving neurons in figure A (n = 3/group). C The percentage of released LDH from OGD/R-treated KO or WT- derived neurons was assessed to determine the neuronal injury in the presence or absence of NMDA (n = 3/group). D Flow cytometry was used to detect the apoptosis of WT or KO-derived neurons pretreated with or without NMDA by PI/Annexin V double labeling. E Quantification of apoptotic cells (Annexin V-positive) in panel C (n = 3/group). F Relative activity of MnSOD, CAT, and GSH content was detected in neurons. Relative activity or content was normalized to the level of WT-derived neurons treated with OGD/R (n = 3/group). G Analysis of ROS production by flow cytometry in KO (left panel) and WT (right panel) derived neurons pretreated with or without NMDA. H Quantification of ROS production in neurons of indicated groups (n = 3/group). Relative fluorescence intensity was normalized to the level of WT neurons that were treated with OGD/R. Statistical analysis: mean ± SEM, *p < 0.05, **p < 0.01, ***p < 0.001