Differential response in the release of hydrogen peroxide between astroglial cells and endothelial cells following hypoxia/reoxygenation.

Hydrogen peroxide (H2O2) and lactate dehydrogenase (LDH) released from cultured astroglial cells (AGs) and brain endothelial cells (BECs) were measured following hypoxia/reoxygenation. AGs released H2O2 to the extracellular space from 8 h of hypoxia with the cellular injury indicated by LDH increase. In contrast, BECs released H2O2 at 4 h of hypoxia, prior to the LDH increase. These results suggest that AGs and BECs play different roles in production and metabolism of oxygen free radicals in the blood-brain barrier (BBB), and AGs may protect the BBB disruption from oxidative stress after hypoxia/reoxygenation.