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目的:探讨邻苯二甲酸二丁酯（dibutyl phthalate，DBP）通过腺苷酸活化蛋白激酶/哺乳动物雷帕霉素靶蛋白（AMP activated protein kinase/mammalian rapamycin target protein，AMPK/mTOR）信号通路对大鼠睾丸间质细胞（Leydig）凋亡的影响。方法:生殖功能损伤大鼠模型按照体质量排序分组法分为模型（DBP）组17只、模型+AMPK抑制剂［DBP+化合物C（compound C，CC）］组17只、模型+AMPK激动剂［DBP+二甲双胍（metformin，MF）］组17只、DBP+AMPK抑制剂+激活剂（DBP+CC+MF）组17只。另取11只大鼠作为空白组。空白组和DBP组腹腔注射等量生理盐水，DBP+CC组、DBP+MF组分别腹腔注射20 mg/kg CC、200 mg/kg MF，DBP+CC+MF组腹腔注射20 mg/kg CC+200 mg/kg MF，qd，连续4周。放射性免疫分析法检测各组血清黄体生成素（luteinizing hormone，LH）、卵泡刺激素（follicle-stimulating hormone，FSH）、睾酮水平；全自动精子质量分析系统分析精子质量；HE染色法观察睾丸生精小管上皮细胞病变情况；末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling，TUNEL）法和流式细胞术检测Leydig细胞凋亡情况；RT-PCR法和Western blotting法检测AMPK、mTOR、半胱氨酸天冬氨酸蛋白酶3（Caspase 3）mRNA和蛋白及p-AMPK、p-mTOR蛋白的表达。结果:与DBP组的血清FSH水平［（9.07±0.52）U/L］相比，DBP+MF组血清FSH水平［（9.88±0.67）U/L］升高，DBP+CC组［（6.82±0.60）U/L］降低，差异均有统计学意义（均n P<0.001）；与DBP组血清LH、睾酮水平、精子浓度及（a+b）级精子占比［（4.51±0.75）U/L、（3.25±0.11）mg/L、（16.46±3.40）×10n 6/mL、（25.43±4.36）%］相比，DBP+MF组血清LH、睾酮水平及精子浓度、（a+b）级精子占比［（3.97±0.70）U/L、（2.96±0.11）mg/L、（13.15±2.63）×10n 6/mL、（22.20±4.13）%］降低，DBP+CC组［（6.52±0.71）U/L、（4.48±0.15）mg/L、（25.47±2.18）×10n 6/mL、（45.60±4.78）%］升高，差异均有统计学意义（DBP组比DBP+MF组n PLH=0.038，其余均n P<0.001）。HE染色显示，空白组睾丸组织结构正常；DBP组和DBP+CC+MF组生精小管上皮细胞萎缩、扭曲呈不规则形态，DBP+MF组病变更为严重，核周现大量空泡；DBP+CC组病变较DBP组有所改善。与DBP组Leydig细胞凋亡数、p-AMPK/AMPK蛋白及n Caspase 3 mRNA和蛋白相对表达量（142.40±26.78、0.70±0.07、1.85±0.14、0.80±0.09）相比，DBP+MF组Leydig细胞凋亡数、p-AMPK/AMPK及n Caspase 3 mRNA和蛋白相对表达量（286.60±30.17、0.95±0.08、2.17±0.18、1.23±0.10）升高，DBP+CC组（88.00±21.34、0.42±0.04、1.35±0.15、0.54±0.06）］降低，差异均有统计学意义（均n P<0.001）；与DBP组p-mTOR/mTOR（0.45±0.06）相比，DBP+MF组（0.23±0.04）降低，DBP+CC组（0.84±0.07）升高（均n P<0.001）。n 结论:DBP可致大鼠生殖系统受损，Leydig细胞凋亡率升高，其机制可能与AMPK活化、mTOR抑制有关。“,”Objective:To explore the effect of dibutyl phthalate (DBP) on the rat testis Leydig cell apoptosis by AMP activated protein kinase/mammalian rapamycin target protein (AMPK/mTOR) signaling pathway.Methods:Rats with reproductive function impairment were divided into model (DBP) group of 17 rats, model+AMPK inhibitor [DBP+compound C (CC)] group of 17 rats, model+AMPK agonist [DBP+metformin (MF)] group of 17 rats, DBP+AMPK inhibitor+agonist (DBP+CC+MF) group of 17 rats by body mass ranking grouping method. Another 11 rats were taken as the blank group. The blank group and DBP group were intraperitoneally injected with the same amount of normal saline, while DBP+CC group and DBP+MF group were intraperitoneally injected with 20 mg/kg CC and 200 mg/kg MF respectively, and DBP+CC+MF group was intraperitoneally injected with CC and MF once a day for 4 weeks. Luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T) were measured by radioimmunoassay. Sperm quality was analyzed by automatic sperm quality analysis system. Leydig cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and flow cytometry. The expressions ofn AMPK, n mTOR, n Caspase 3 mRNA and protein, p-AMPK and p-mTOR protein were detected by RT-PCR and Western blotting.n Results:The serum level of FSH in DBP+MF group [(9.88±0.67) U/L] increased, while that in DBP+CC group [(6.82±0.60) U/L] decreased compared with DBP group [(9.07±0.52) U/L] (alln P<0.001). The serum LH, T levels and sperm concentration, percentage of (a+b) grade sperm in DBP+MF group [(3.97±0.70) U/L, (2.96±0.11) mg/L, (13.15±2.63)×10n 6/mL, (22.20±4.13)%], DBP+CC group [(6.52±0.71) U/L, (4.48±0.15) mg/L, (25.47±2.18)×10n 6/mL, (45.60±4.78)%] increased compared with DBP group [(4.51±0.75) U/L, (3.25±0.11) mg/L, (16.46±3.40)×10n 6/mL, (25.43±4.36)%] (DBP group n vs. DBP+MF group n PLH=0.038, the other all n P<0.001). HE staining showed that the structure of testis in blank group was normal. In DBP group and DBP+CC+MF group, the epithelial cells of seminiferous tubules atrophied and twisted in irregular shape, and the disease became serious in DBP+MF group, and there were a lot of vacuoles around the nucleus. The number of apoptosis, p-AMPK/AMPK protein relative expression andn Caspase 3 mRNA and protein relative expression of Leydig cells in DBP+MF group (286.60±30.17, 0.95±0.08, 2.17±0.18, 1.23±0.10) increased, and DBP+CC group (88.00±21.34, 0.42±0.04, 1.35±0.15, 0.54±0.06) decreased compared with those in DBP group (142.40±26.78, 0.70±0.07, 1.85±0.14, 0.80±0.09, all n P<0.001). Compared with DBP group (0.45±0.06), the p-mTOR/mTOR of DBP+MF group (0.23±0.04) decreased, and the p-mTOR/mTOR of DBP+CC group (0.84±0.07) increased (alln P<0.001).n Conclusion:DBP can damage the reproductive system of rats and increase the apoptosis rate of Leydig cells, which may be related to AMPK activation and mTOR inhibition.