Objective    To explore the relationship between seizure susceptibility and PSD-95 expression in rats following hypoxic brain injury.      Methods    Male SD rats were divided into the control group and the hypoxia group. The hypoxic brain injury model was established by exposing the rats to global hypoxia induced by 8% nitrogen oxygen atmosphere. Pentylenetetrazol (PTZ) [10 mg/(kg·5 min) and 35 mg／(kg·2d)] were injected intraperitoneally into the rats from both groups to test the number of kindling

seizure stage and seizure threshold. The neuronal loss and PSD-95 expression in the temporal cortex

hippocampal CA1 subfield and midbrain were studied by using immunohistochemistry and Western blotting

respectively.      Results    The rats exposed to hypoxia exhibited increased seizure susceptibility to PTZ. Associated with this change in seizure susceptibility

neuronal loss was observed in the temporal cortex

hippocampal CA1 subfield and midbrain region in hypoxic rats and post-hypoxic kindling rats while PSD-95 expression was reduced in the both temporal cortex and hippocampus in hypoxic rats.      Conclusion    Neuronal loss is associated with the increased seizure susceptibility in adult rats following hypoxic cerebral injury. The decreased expression of PSD-95

as the consequence of hypoxic damage

may at least in part

contribute to hypoxia-induced reduction in seizure threshold.