锰锌联合作用下大鼠生精细胞caspase-3和cyto-c的表达变化

目的研究锰和锌对生精细胞caspase-3、cyto-c表达的影响。方法健康雄性SD大鼠80只随机分为10组,空白对照组,ZnCl2对照组,15 mg.kg-1和30 mg.kg-1MnCl2组;15 mg.kg-1MnCl2＋ZnCl2组和30 mg.kg-1MnCl2＋ZnCl2组。锰组分别给予MnCl2.4H2O腹腔注射4周和6周;ZnCl2对照组给予100 mg Zn2＋.kg-1饲料口服;锰加锌组分别染锰4周后再给予含锌饲料口服。各组大鼠分别于第4周末和第6周末处死,免疫组化法检测睾丸caspase-3、cyto-c表达。结果与空白组比较,各锰组和锰加锌组caspase-3阳性细胞率均升高,cyto-c阳性细胞率均降低（P〈0.01）。与同剂量组比较,染锰6周caspase-3和cyto-c阳性细胞率分别较4周升高和降低（P〈0.01）。与同时间组比较,30 mg.kg-1组caspase-3和cyto-c阳性细胞率分别较15 mg.kg-1组升高和降低（P〈0.01）。与同剂量锰组比较,锰加锌组caspase-3和cyto-c阳性细胞率分别降低和升高。各组caspase-3和cyto-c阳性细胞率呈负相关（r=-0.817,P〈0.01）。结论 15 mg.kg-1和30 mg.kg-1氯化锰均可诱发大鼠生精细胞caspase-3和cyto-c表达,并随染锰时间和剂量的增加而分别增加和降低,存在一定的时间-效应和剂量-效应关系,摄入含锌100 mg.kg-1的食物可抑制锰所诱发的caspase-3表达。

Changes of Caspase-3 and Cyto-c in Spermatogenic Cells of Rats Exposing to Manganese and Zinc

Objective To study the effects of Mn and Zn on the expression of caspase-3 and cyto-c in spermatogenic cells of male rat and to discuss its mechanisms.Methods 80 healthy male rats were randomly divided into 10 groups(blank control,ZnCl2 control,15 mg·kg-1 and 30 mg·kg-1 MnCl2,15 mg·kg-1 MnCl2+ZnCl2 and 30 mg·kg-1 MnCl2+ZnCl2).After having MnCl2 by I.P.injection for 4 and 6 weeks respectively,15 mg·kg-1 and 30 mg·kg-1+Zn groups were feeded with zinc forage(Zn2+100 mg) orally for 2 weeks,blank control group was injected with NS,and ZnCl2 control group was feeded with zinc.In the 4th and 6th weekend,the expression of caspase-3 and cyto-c in testes were investigated by immunohistochemical methods(SABC).Results Compared with blank control group,the expression of caspase-3 increased as well as cyto-c decreased in every Mn and Mn+Zn groups(P<0.01).Compared with manganese groups of same dose,caspase-3 increased but cyto-c decreased in six-week group(P<0.01).Compared with Mn groups of same time,caspase-3 increased but cyto-c decreased in 30 mg·kg-1 groups(P<0.01).Compared with manganese exposure groups of same dose,caspase-3 decreased but cyto-c increased in Mn+Zn groups(P<0.01).There was a negative correlation between the expression of caspase-3 and cyto-c(r=-0.837,P<0.01).Conclusion MnCl2 may induce the expression of caspase-3 and cyto-c of rat spermatogenic cells,there is dose-effect and time-effect relationship between them.100 mg·kg-1 zinc can antagonize the expression of caspase-3 induced by manganese.