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| Changes of EphA4,ephrinA3 Expression in Hippocampal CA1 Region of Epileptic Rats Induced by Pilocarpine and its Significance |
| ZHANG Meng-qi, DING Hui, LI Shu-yu, et al |
| Department of Neurology, the Xiangya Hospital, Central Southern University, Changsha 410008, China |
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Abstract 【Objective】 To investigate the changes and significance of EphA4,ephrinA3 expression in hippocampal CA1 region of epileptic rats induced by pilocarpine.【Methods】 The SD rat model of temporal lobe epilepsy was established by pilocarpine. The changes of EphA4 protein and ephrinA3 gene in hippocampal CA1 at different time points were detected by immunohistochemistry and in situ hybridization.The morphological changes of dendritic spine in CA1 region were observed by rapid Golgi staining and the dynamic changes of ephrinA3 in astrocytes were observed by confocal microscopy.【Results】 The expression of EphA4 and ephrinA3 in hippocampal CA1 was high in temporal lobe epilepsy rats. Compared with the control group, the expression of EphA4 protein and ephrinA3 mRNA decreased to the lowest point at 7 days after epilepsy (P<0.01). After that, it increased gradually, but it was still lower than the control group at 15 days (P<0.05), and returned to that of the control group at 30 and 60 days (P>0.05). The dendritic spine of pyramidal cells in CA1 area became thinner, longer and denser at 7 days after epilepsy. EphrinA3 was expressed in the astrocytes of the hippocampus of the mature rats. The expression of ephrinA3 in the astrocytes of the hippocampus of the rats was down-regulated 7 days after epilepsy, and increased at 15 days after epileptic status, but it was still lower than that of the control group and returned to normal at 30 days.【Conclusion】 The down-regulation of the expression of EphA4 protein and ephrinA3 mRNA in CA1 participates in the regulation of postsynaptic dendritic spine morphology and is one of the important molecules regulating synaptic plasticity.
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Received: 19 June 2018
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2018, Vol. 35 
