Objective To observe the expression of peroxisome proliferator-activated receptor γ (PPARγ) in hippocampus neurons in rats after different time of neuron oxygen deprivation/oxygen supply, and to investigate the role of PPARγ in neuron ischemia reperfusion injury.Methods One day old newborn SD rats were chosen. Primary cultured hippocampus neurons were used to establish neuron ischemic reperfusion model in vitro by oxygen and glucose depriving 15 minutes and supplying again, and then the neuron structure was observed by transmission electron microscope of JEM-200EX.The expression of PPARγ mRNA and protein were detected by RT-PCR and Western blot, respectively.Results Neuron structure was damaged after neuron oxygen deprivation/oxygen supply. There was no significant difference between 0 h oxygen supply group and the control group.The expression of PPARγ was decreased both at mRNA and protein level after 6 h of oxygen supply. The difference between 6 h oxygen supply group and the control group was significant(P<0.01), which decreased with the length of reperfusion and the lowest was at 48 h after the reperfusion. The difference among the different reperfusion groups and the control group was significant(P<0.01). Conclusion PPARγ may participate in the pathological damage course of neuron ischemical reperfusion injury, and may become a new intervention target of treatment for ischemic cerebrovascular disease.