目的 了解环境内分泌干扰因子邻苯二甲酸二乙基已酯(DEHP)及代谢产物邻苯二酸-单-2-乙基己酯(MEHP)对雄性幼鼠生精细胞凋亡有否影响.方法 生后2周龄的Wistar雄性幼鼠98只,随机分为14组,7只/组.随机选择1组行生理盐水(0.9％NS 0.2 ml·kg-1·d-1)灌胃喂养3周,作为正常对照组(NC组)；再选1组行环磷酰胺(CTX 100 mg·kg-1·d-1)灌胃喂养1周,作为阳性对照组(PC组)；余各组分别用DEHP、MEHP按低剂量(100 mg· kg-1·d-1)、中剂量(200 mg·kg-1·d-1)、高剂量(300 mg·kg-1·d-1)灌胃喂养1周；以及分别按低剂量(100mg·kg-1·d-1)灌胃喂养1、2、3周分组,建立动物模型.观察不同时期、不同剂量下睾丸生精细胞的形态学变化,并应用TUNEL法检查睾丸生精细胞凋亡情况,放射免疫法检测血清性激素(卵泡刺激素FSH、黄体生成素LH以及睾酮T)水平.结果 (1)睾丸生精细胞的变化:用药组生精细胞萎缩、发育落后、数量少,线粒体肿胀、空泡化等；在喂养1周的不同剂量组内,随剂量增加生精细胞损害加重,在低剂量不同喂养时间组内,随喂养时间的延长生精细胞损害亦加重；(2)睾丸组织中生精细胞凋亡:与NC组比较,用药组生精细胞凋亡显著增多(P＜0.01)；在喂养1周的不同剂量组内、以及低剂量不同喂养时间组内生精细胞凋亡间比较,差异均有统计学意义(P＜0.05)；(3)血清性激素水平:与NC组比较,用药组FSH、LH水平升高,T水平下降(P＜0.05)；在喂养1周的不同剂量组内、以及低剂量不同喂养时间组内性激素水平间比较,差异也有统计学意义(P＜0.05).结论 DEHP及代谢产物MEHP对幼鼠生精细胞凋亡有明显影响,且呈时间-量效依赖效应.%Objective To explore the influences of di-(2-ethylhexyl)phthalate (DEHP) and its principle metabolite mono (2-ethylhexyl)phthalate (MEHP) on spermatogenic cell apoptosis in young male Wistar rats. Methods Ninety-eight 2-week-old male Wistar rats were randomly divided into 14 equal groups to receive daily intragastric administration of 0.2 ml/kg normal saline for 3 weeks (normal control), 100 mg/kg cyclophosphamide (CTX) for 1 week (positive control), 100, 200, and 300 mg/kg DEHP or MEHP for 1 week, or 100 mg/kg DEHP or MEHP for 1, 2, and 3 weeks. After the treatments, the pathological changes of the testicular tissues were examined, spermatogenic cell apoptosis was detected, and serum sex hormones levels were measured using TUNEL assay or radioimmunoassays. Results CTX, DEHP, and MEHP all caused shrinkage, development retardation and quantitative reduction of spermatogenic cells with and mitochondrial swelling vacuolar changes. The damage of spermatogenic cells increased significantly with the increment of DEHP and MEHP doses and exposure time. Both DEHP and MEHP treatments resulted in significantly increased cell apoptosis index (AI) in close correlation with the exposure doses and duration (P<0.01). DEHP and MEHP treatments also significantly increased serum levels of follicle stimulating hormone and luteinizing hormone and decreased testosterone levels in a dose- and time-dependent manner (P<0.05). Conclusion DEHP and MEHP can induce obvious apoptosis of spermatogenic cells in young male rats with a dose- and time-dependent effect.
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