Background & objectives: Brain ischemia leads to irreversible functional and structural damage in various regions of the brain, especially in the hippocampus. There is an evidence indicating the physical exercise has neuroprotective effects and may decrease the cerebral ischemia/ reperfusion injury in rats. The purpose of this study was the study of the effect of exercise preconditioning on memory deficits and neuronal cell death in CA3 pyramidal cells of the rat hippocampus following transient global ischemia.

  Methods: 21 male rats weighing 260-300g were randomly selected and allocated into three groups (sham, ischemia and exercise+ischemia). The rats in exercise group were trained to run on a treadmill 5 days a week for 4 weeks. Ischemia induced by occlusion both common carotid arteries (CCA) for 20 minutes. The passive avoidance memory test using a Shuttle box used to assess the impairment of memory. The amount of cell death was measured using cresyl violet staining method.

  Results: The results showed that cerebral ischemia is associated with memory impairment, and physical activity before ischemia improves ischemia-induced memory impairments significantly (p<0.05). In addition, ischemia leads to cell death in hippocampal CA3 area neurons and exercise also reduces ischemia-induced cell death significantly (p<0.05).

  Conclusion: This study showed that exercise, when is used as a preconditioning stimulant , has a neuroprotective effects against brain ischemia.