丙烯腈对大鼠睾丸抗氧化酶活力和脂质过氧化水平的影响

目的　探讨丙烯腈(ACN)的雄性生殖毒性机制。方法　健康雄性SD大鼠分别以0、7.5、15.0、30.0 mg/kg剂量腹腔注射ACN染毒,测定其睾丸谷胱甘肽(GSH)、丙二醛(MDA)含量和超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH Px)、谷胱甘肽S 转移酶(GST)活力。结果　ACN染毒4周后,15.0、30.0 mg/kg组大鼠睾丸GSH含量(7.44±0.96)、(6.95±0.77)mg/g pro]增加,30.0 mg/k组大鼠GSH Px活力(70.89±4.01)U/mg pro]升高,与对照组的差异均有统计学意义(P<0.05,P<0.01)。ACN染毒8周后,30.0 mg/kg组大鼠睾丸GSH含量(2.50±0.94)mg/g pro]降低,15.0、30.0mg/kg组大鼠SOD活力(102.08±16.08)、(113.30±17.20)NU/mg pro]升高,与对照组的差异均有统计学意义(P<0.01)。ACN染毒13周后,15.0、30.0 mg/kg组大鼠睾丸GSH含量降低,30.0 mg/kg组GST活力下降,各染毒组GSH Px活力均低于对照组,30.0 mg/kg组MDA含量(0.68±0.16)nmol/mgpro]高于对照组(0.38±0.12)nmol/mg pro],差异均有统计学意义(P<0.01)。停止染毒后2周,大鼠睾丸GSH水平恢复;30.0 mg/kg组大鼠睾丸MDA含量下降,但仍高于对照组,GSH Px活力仍低于对照组,差异均有统计学意义(P<0.05)。结论　ACN能通过破坏氧化-抗氧化体系的平衡,诱导雄性大鼠睾丸脂质过氧化损伤。

Effects of acrylonitrile on the activities of antioxidant enzymes and levels of lipid peroxidation in rat testes

OBJECTIVE: To explore the mechanism of male reproductive toxicity induced by acrylonitrile (ACN). METHODS: Male Sprague-Dawley rats were daily administrated ACN by intraperitoneal injection 5 times a week for 13 weeks at the dose of 0, 7.5, 15.0 and 30.0 mg/kg body weight, respectively. The rats were sacrificed and testes were removed at the end of 4, 8, 13 or 15 weeks, respectively. The activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione S-transferase (GST) and the levels of glutathione (GSH) and malonaldehyde (MDA) were detected in testes. RESULTS: Following ACN treatment of 4 weeks, the levels of GSH in ACN 15.0 mg/kg and 30.0 mg/kg group were (7.44 +/- 0.77) mg/g pro and (6.95 +/- 0.77) mg/g pro respectively, and the activity of GSH-Px was (70.89 +/- 4.01) U/mg pro in 30.0 mg/kg group, all of which were significantly higher than the control group (P < 0.05, P < 0.01). After 8 weeks, the levels of GSH decreased to (2.50 +/- 0.94) mg/g pro in ACN 30.0 mg/kg group (P < 0.01); the activities of SOD increased to (102.08 +/- 16.08) NU/mg pro and (113.30 +/- 17.20) NU/mg pro in ACN 15.0 mg/kg and 30.0 mg/kg group (P < 0.01). After 13 weeks, the levels of GSH declined in ACN 15.0 mg/kg and 30.0 mg/kg group, and the activities of GST decreased in ACN 30.0 mg/kg group, and of GSH-Px decreased in both doses group. However, the level of MDA (0.68 +/- 0.16) nmol/mg pro] were significantly higher in 30.0 mg/kg group than that in control group (0.38 +/- 0.12) nmol/mg pro] (P < 0.01). 2 weeks after stopping ACN treatment, the level of GSH restored to normal but the levels of MDA or the activity of GSH-Px in 30.0 mg/kg group were still higher or lower respectively than those of control (P < 0.05). CONCLUSION: ACN may impair the balance of antioxidant system, thus induce lipid peroxidation damage to rat testes.