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目的:探讨N-myc下游调节基因2(N-myc downstream regulated gene 2，NDRG2)在癫痫小鼠海马中的表达及其对小鼠脑星形胶质细胞谷氨酸和葡萄糖摄取的影响。方法:采用氯化锂-匹鲁卡品诱导法建立癫痫小鼠模型，在造模后1 d、7 d、15 d、6周处死小鼠取取海马区脑组织，Western blot检测NDRG2蛋白表达变化。原代培养野生型、NDRG2n ＋/＋和NDRG2n -/-小鼠的星形胶质细胞并进行基因型鉴定。使用谷氨酸含量测定试剂盒及紫外分光光度计检测星形胶质细胞培养上清液中谷氨酸含量。流式细胞术检测2-NBDG荧光标记星形胶质细胞的阳性率。n 结果:(1)与对照组(0.25±0.07)比较，小鼠海马区NDRG2表达量在癫痫急性期1 d(0.45±0.06，n t＝－3.84，n P<0.05)、7 d(0.54±0.09，n t＝－4.30，n P<0.05)、15 d(1.04±0.06，n t＝－15.08，n P<0.01)均有明显增加，癫痫慢性期6周(1.30±0.16，n t＝－10.40，n P<0.01)依然保持明显的高表达。(2)检测原代细胞培养上清液剩余的谷氨酸含量，发现NDRG2n -/-组星形胶质细胞对谷氨酸的摄取相对于NDRG2n ＋/＋组明显减少[(689.03±101.78)μmol/L，(113.67±37.35)μmol/L；n t＝9.19，n P<0.01]。(3)Western blot分析NDRG2n -/-组原代星形胶质细胞中EAAT1蛋白的表达显著低于NDRG2n ＋/＋组[(0.34±0.03)，(1.16±0.21)]，差异有统计学意义(n t＝－6.59，n P<0.01)。(4)流式细胞术检测发现，NDRG2n -/-组细胞的阳性率明显低于NDRG2n ＋/＋组细胞阳性率[(17.60±5.72)%，(72.22±8.35)%]，差异有统计学意义(n t＝－13.22，n P<0.01)。n 结论:NDGR2与癫痫疾病的发生发展密切相关。NDRG2的表达有利于EAAT1发挥其生理功能，促进星形胶质细胞对谷氨酸和葡萄糖的摄取，可能是一种潜在细胞保护因子，促进神经保护和修复。“,”Objective:To investigate the expression of N-myc downstream regulated gene 2(NDRG2) in hippocampus of epileptic mice and its effect on glutamate and glucose uptake in astrocytes of mice.Methods:The epileptic mouse model was induced by lithium chloride and pilocarpine nitrate. The mice were sacrificed at 1 d, 7 d, 15 d and 6 weeks after model establishment and the brain tissues of hippocampus were taken. Western blot was used to detect the expression of NDRG2 protein in hippocampus.The primary astrocytes of wild-type, NDRG2n + /+ and NDRG2n -/- mice were cultured and the NDRG2 phenotype of astrocytes was identified after primary culture. Glutamate content in the supernatant of astrocyte culture was determined by glutamate assay kit and ultraviolet spectrophotometer. Flow cytometry was used to detect the positive rate of 2-NBDG fluorescently labeled astrocytes.n Results:(1) Compared with the control group (0.25±0.07), the expression of NDRG2 in the hippocampus of mice increased significantly in the acute phase of epilepsy (1 d(0.45±0.06, n t=-3.84, n P<0.05), 7 d(0.54±0.09,n t=-4.30, n P<0.05), 15 d(1.04±0.06,n t=-15.08, n P<0.01)), and remained significantly high in the chronic phase of epilepsy( 6 weeks (1.30±0.16,n t=-10.40, n P<0.01)). (2) The content of residual glutamate in the supernatant fluid of primary cell culture medium was detected.It was found that the uptake of glutamate by astrocytes in the NDRG2n -/- group was significantly lower than that in the NDRG2n + /+ group ((689.03±101.78) μmol/L, (113.67±37.35) μmol/L; n t=9.19, n P<0.01). (3) Western blot results showed that the expression of EAAT1 protein in NDRG2n -/- primary astrocyte was significantly lower than that of NDRG2n + /+ primary astrocyte(0.34±0.03, 1.16±0.21), and the difference was statistically significant (n t=-6.59, n P<0.01). (4) Flow cytometry results showed that the positive rate of astrocyte in NDRG2n -/- group cells was significantly lower than that in NDRG2n + /+ group cells ((17.60±5.72)%, (72.22±8.35)%), and the difference was statistically significant (n t=-13.22, n P<0.01).n Conclusion:NDGR2 is closely related to the occurrence and development of epileptic diseases. The expression of NDRG2 is beneficial to exert its physiological function of EAAT1 and promotes the uptake of glutamate and glucose by astrocyte. It may be a potential cell protective factor to promote nerve protection and repairment.