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目的:探讨亚砷酸钠（NaAsOn 2）暴露对小鼠淋巴结血管内皮细胞系SVEC4-10细胞中核因子E2相关因子2（Nrf2）信号通路转录活性的影响。n 方法:采用细胞体外培养方法，分别以不同剂量NaAsOn 2[0（对照）、2、5、10、20、50、100、150 μmol/L]处理SVEC4-10细胞24 h，四唑化合物（MTS）法检测细胞活性。时间-效应关系研究分别以5 μmol/L NaAsOn 2处理SVEC4-10细胞0（对照）、2、6、12 h。剂量-效应关系研究分别以0（对照）、2、5、10 μmol/L NaAsOn 2处理SVEC4-10细胞6 h。采用实时荧光定量PCR（RT-qPCR）法检测Nrf2信号通路相关基因Nrf2、谷氨酰半胱氨酸连接酶催化亚单位（Gclc）、谷氨酰半胱氨酸连接酶修饰亚单位（Gclm）、醌氧化还原酶1（Nqo1）、金属硫蛋白1（Mt1）mRNA水平。采用SVEC4-10细胞建立Nrf2基因稳转沉默（Nrf2-KD）细胞，分别以0（对照）、10、20 μmol/L NaAsOn 2处理干扰对照（scramble，SCR）细胞和Nrf2-KD细胞16 h，流式细胞仪检测细胞凋亡情况。n 结果:MTS检测结果显示，对照组，2、5、10、20、50、100、150 μmol/L NaAsOn 2处理组细胞活性分别为（100.00 ± 19.53）%、（98.18 ± 9.85）%、（96.09 ± 30.04）%、（90.64 ± 8.74）%、（59.75 ± 12.09）%、（35.43 ± 8.58）%、（26.35 ± 5.89）%、（17.54 ± 4.48）%，不同剂量组间细胞活性比较差异有统计学意义（n F = 18.30，n P < 0.05）；且20、50、100、150 μmol/L NaAsO n 2处理组细胞活性显著低于对照组（n P均< 0.05）。时间-效应关系研究结果显示，对照组，2、6、12 h处理组组间Nrf2、Gclc、Gclm、Nqo1、Mt1 mRNA水平比较差异有统计学意义（n F = 56.69、85.28、90.82、80.46、758.60，n P均< 0.05）；随着砷暴露时间的延长，Nrf2、Gclc、Gclm、Mt1 mRNA水平先上升后下降，Nqo1 mRNA水平不断上升；其中，Nrf2 mRNA水平在2 h达到峰值，Gclc、Gclm、Mt1 mRNA水平在6 h达到峰值，Nqo1 mRNA水平在12 h达到峰值。剂量-效应关系研究结果显示，对照组，2、5、10 μmol/L NaAsOn 2处理组组间Nrf2、Gclc、Gclm、Nqo1、Mt1 mRNA水平比较差异有统计学意义（n F = 68.39、72.26、30.41、397.00、28.88，n P均< 0.05）；随着砷暴露剂量增加，Nrf2、Gclc、Gclm、Nqo1、Mt1 mRNA水平有所上升，其中Nrf2 mRNA水平在5 μmol/L剂量时达到峰值，Gclc、Gclm、Nqo1、Mt1 mRNA水平在10 μmol/L剂量时达到峰值。细胞凋亡检测结果显示，对照组，10、20 μmol/L NaAsOn 2处理组组间SCR、Nrf2-KD细胞凋亡率比较差异有统计学意义（n F = 8.18、9.66，n P均< 0.05）；与对照组比较，20 μmol/L NaAsOn 2处理组SCR、Nrf2-KD细胞凋亡率升高（n P均< 0.05）；且20 μmol/L NaAsOn 2处理组Nrf2-KD细胞凋亡率高于同剂量组的SCR细胞（n P < 0.05）。n 结论:NaAsOn 2暴露引起小鼠淋巴结血管内皮细胞系SVEC4-10细胞Nrf2信号通路活化，激活适应性抗氧化反应，改变转录活性；而Nrf2的沉默使SVEC4-10细胞对NaAsOn 2毒性更为敏感。n “,”Objective:To investigate the effect of sodium arsenite (NaAsOn 2) on transcriptional activity of nuclear factor E2-related factor 2 (Nrf2) signaling pathway in mouse lymph node vascular endothelial cell line (SVEC4-10).n Methods:In vitro cell culture method was used to treat SVEC4-10 cells for 24 h with different doses of NaAsOn 2 [0 (control), 2, 5, 10, 20, 50, 100, 150 μmol/L], and the cell viability was detected by tetrazole compound (MTS) method. The time-response relationship was studied with SVEC4-10 cells treated with 5 μmol/L NaAsO n 2 for 0 (control), 2, 6 and 12 h; the dose-response relationship was studied with SVEC4-10 cells treated with 0 (control), 2, 5 and 10 μmol/L NaAsO n 2 for 6 h; real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the mRNA expression of Nrf2 and its downstream genes glutamate-cysteine ligase catalytic subunit (Gclc), glutamate-cysteine ligase modifier subunit (Gclm), NAD(P)H dehydrogenase quinone 1 (Nqo1) and metallothionein 1 (Mt1). Establishment of Nrf2 gene stably silenced (Nrf2-KD) cells using SVEC4-10 cells, the interference control (scramble, SCR) cells and Nrf2-KD cells were treated with 0(control), 10 and 20 μmol/L NaAsO n 2 for 16 h, and apoptosis was detected by flow cytometry.n Results:MTS test results showed that the cell viability of the control, 2, 5, 10, 20, 50, 100, 150 μmol/L NaAsO n 2 treatment groups was (100.00 ± 19.53)%, (98.18 ± 9.85)%, (96.09 ± 30.04)%, (90.64 ± 8.74)%, (59.75 ± 12.09)%, (35.43 ± 8.58)%, (26.35 ± 5.89)% and (17.54 ± 4.48)%, respectivily. There was statistically significant difference in cell viability between different dose groups (n F = 18.30, n P < 0.05); and the cell viability of the 20, 50, 100, 150 μmol/L NaAsO n 2 treatment groups was significantly lower than that of the control group (n P < 0.05). The time-response relationship results showed that there were statistically significant differences in Nrf2, Gclc, Gclm, Nqo1 and Mt1 mRNA level between control, 2, 6 and 12 h treatment groups ( n F = 56.69, 85.28, 90.82, 80.46, 758.60, n P < 0.05); with extension of arsenic exposure time, the mRNA level of Nrf2, Gclc, Gclm and Mt1 first increased and then decreased, the mRNA level of Nqo1 increased continually; among them, the mRNA level of Nrf2 peaked at 2 h, the mRNA levels of Gclc, Gclm and Mt1 peaked at 6 h, and the mRNA level of Nqo1 peaked at 12 h. The dose-response relationship results showed that there were statistically significant differences in Nrf2, Gclc, Gclm, Nqo1 and Mt1 mRNA levels between control, 2, 5 and 10 μmol/L NaAsO n 2 treatment groups (n F = 68.39, 72.26, 30.41, 397.00, 28.88, n P < 0.05); with increasing of arsenic exposure dose, the mRNA levels of Nrf2, Gclc, Gclm, Nqo1 and Mt1 increased. The mRNA level of Nrf2 peaked at a dose of 5 μmol/L, and the mRNA levels of Gclc, Gclm, Nqo1 and Mt1 peaked at a dose of 10 μmol/L. Apoptosis test results showed that there were statistically significant differences in the apoptosis rates of SCR and Nrf2-KD cells between control, 10 and 20 μmol/L NaAsO n 2 treatment groups (n F = 8.18, 9.66, n P < 0.05); compared with the control group, the apoptosis rates of SCR and Nrf2-KD cells in the 20 μmol/L NaAsO n 2 treatment group increased (n P < 0.05); and the apoptosis rate of Nrf2-KD cells in the 20 μmol/L NaAsO n 2 treatment group was higher than that of SCR cells in the same dose group (n P < 0.05).n Conclusions:NaAsOn 2 exposure has caused the activation of Nrf2 signaling pathway in mouse lymph node vascular endothelial cell line SVEC4-10 cells, activated the adaptive antioxidant response, and altered transcriptional activity; while silence of Nrf2 has made SVEC4-10 cells more sensitive to NaAsOn 2 toxicity.n