大鼠新生期苯并芘暴露对睾丸抗氧化酶活性和精子生成量的影响  

Effects of Benzo(a)pyrene Exposure on Testicular Antioxidant Enzyme Activities in Neonatal SD Rats

作　　者：梁继仁[1] 朱鸿雁[1] 李翠珍[1] 周志俊[1] 吴庆[1] 

机构地区：[1]复旦大学公共卫生学院,公共卫生安全教育部重点实验室,上海200032

出　　处：《环境与职业医学》2012年第5期290-293,共4页Journal of Environmental and Occupational Medicine

基　　金：国家自然科学基金资助项目(编号:20977019)

摘　　要：[目的]探讨SD大鼠新生期苯并芘暴露对抗氧化酶活性和精子生成量的影响。[方法]自大鼠出生后第1天起连续7d给予0、5、10和25mg/kg 3,4-苯并芘灌胃,在出生后第8、35和90天解剖大鼠,脏器称重并计算脏器系数和每日精子生成量。测定睾丸中(出生后第8、35和90天)CYP1A1基因表达和超氧化物歧化酶(superoxide dismutase,SOD)及过氧化氢酶(catalase,CAT)活性。[结果]连续染毒7d,在出生后第8天,睾丸中细胞色素P450氧化酶基因(CYP1A1基因)表达随暴露剂量升高而上升,且10和25mg/kg暴露组基因表达量与对照组相比,差异均有统计学意义(P<0.05);在出生后第35和90天时,各组睾丸中CYP1A1基因几乎没有表达。SOD、CAT活性测定显示:在出生后第8天,与对照组比,25mg/kg组的SOD活性上升(P<0.05),虽然各暴露组CAT活性与对照组相比差异无统计学意义,但是随着剂量的增大,CAT活性呈上升趋势;出生后第35天时,与对照组相比,各剂量组SOD、CAT活性均明显下降(P<0.05);在出生后第90天,SOD、CAT活性变化与对照组比较,差异无统计学意义。出生后第90天时,苯并芘10和25mg/kg暴露组每日精子生成量较对照组下降(P<0.05)。[结论]SD大鼠新生期暴露苯并芘可导致成年期睾丸每日精子生成量下降,影响睾丸抗氧化酶SOD和CAT的活性。[ Objective ] To investigate the changes of antioxidant enzyme activities in testis of SD rats after neonatal exposure to 3, 4-benzo（a）pyrene. [ Methods ] The neonatal rats were treated with benzo（a）pyrene in corn oil by gavages at doses of 0, 5, 10 and 25 mg/kg from postnatal day 1 to day 7. They were sacrificed at postnatal day 8, 35 and 90. Organ weights, daily sperm production, enzyme activities of superoxide dismutase （SOD） and catalase （CAT）, and CYP1A1 gene expression levels of testis were determined at postnatal day 8, 35 and 90. [ Results ] CYP1A1 gene expressions in exposed groups were induced in a dose-dependent manner at postnatal day 8, and that of the 10 and 25 mg/kg groups were significantly higher than that of the controls （P〈0.05）, but there was barely no CYPIA1 gene expression in groups at postnatal day 35 and 90. At postnatal day 8, SOD enzyme activities in 25 mg/kg group were increased significantly than that in the controls （P〈0.05）; and CAT enzyme activities were increased with exposure doses; at postnatal day 35, the activities of both SOD and CAT decreased significantly than that of the controls （P 〈 0.05）; at postnatal day 90, there was significant difference in neither SOD nor CAT enzyme activities between exposure groups and controls; and the number of daily sperm production of 10 and 25 mg/kg groups decreased significantly （P〈 0.05）. [ Conclusion ] Neonatal exposure to benzo（a）pyrene altered activities of SOD and CAT enzymes in testis, and decreased daily sperm production.

关 键 词：苯并芘 新生期暴露 精子计数 超氧化物歧化酶 过氧化氢酶 细胞色素P450氧化酶基因 

分 类 号：R114[医药卫生—卫生毒理学]