丙烯腈对小鼠生精细胞Bcl-2、Bax蛋白表达的影响

目的探讨丙烯腈(AN)暴露对小鼠睾丸生精细胞Bcl-2、Bax蛋白表达水平的影响。方法将250只成年健康SPF级昆明种雄性小鼠,按体重随机分为阴性对照组、3个AN染毒组和阳性对照组,阴性对照组用生理盐水,各染毒组分别以1.25、2.50、5.00mg/kg AN腹腔注射(注射剂量为0.01ml/g BW),每天1次,连续5天,阳性对照组注射环磷酰胺40mg/kg一次。分别于首日染毒后的第7、14、21、28和35天采用颈椎脱臼法处死小鼠,采用免疫组织化学法(SABC)检测生精细胞Bcl-2和Bax蛋白的表达。结果 5个观察时间点AN 2.50mg/kg组和21天AN 1.25mg/kg组Bcl-2平均光密度值均显著低于阴性对照组(P<0.05);除21天AN 1.25mg/kg组外,所有观察时间点AN各染毒组Bax平均光密度值均显著高于阴性对照组(P<0.05)。Bcl-2在中剂量组和阳性对照组各观察时间点降低幅度均较大;Bax在各剂量组的不同时间点均以14天时升高幅度最大。结论 AN可诱导生精细胞Bcl-2蛋白表达减弱,以AN 2.50mg/kg组最为显著;同时可诱导生精细胞Bax蛋白表达增强,以14天时变化幅度较明显。

Effect of acrylonitrile on the expression of Bcl-2 and Bax in spermatogenic cell of mice

Objective To explore the effect of acrylonitrile exposure on the expression of Bcl-2 and Bax in mice spermatogenic cells.Methods Based on body weight,250 SPF Kunming adult male mice were randomly divided into five groups: negative control group(normal saline 0.01ml/g),three AN exposure groups(intraperitoneal injection of 1.25,2.50 or 5.00 mg/kg of AN daily for 5 days,respectively)and positive control group(intraperitoneal injection of cyclophosphamide 40mg/kg).Mice were killed in the 7th,14th,21st,28th and 35th day after the first exposure by cervical dislocation.Immunohistochemical method(SABC) was used to detect the expression of Bcl-2 and Bax protein in spermatogenic cells.Results The average optical density values of Bcl-2 at five time points of the AN 2.50 mg/kg group and the 21th day point of the AN 1.25mg/kg group were significantly lower than the negative control group(P<0.05).Except the 21st day point of the AN 1.25 mg/kg group,the mean optical density values of Bax in all time points of AN exposure groups were significantly higher than the negative control group(P<0.05).The decreased expression of Bcl-2 protein was most distinct in AN 2.50mg/kg group and the positive control group at all time points.The expression of Bax protein was significantly increased in all groups at the 14th day point.Conclusion The expression of Bcl-2 protein could be weakened in spermatogenic cells induced by AN,especially in the AN 2.50 mg/kg group;while the expression of Bax was enhanced,and the amplitude of change in the 14th day point was more obvious.