多氯联苯对孔雀鱼卵黄蛋白原的诱导及检测

为探讨利用孔雀鱼(Poecilia reticulata)卵黄蛋白原(Vitellogenin,Vtg)作为生物标志物检测环境雌激素的可行性,采用浸浴法分别使用17β-雌二醇(E2)和多氯联苯(PCBs)对雄性孔雀鱼成鱼进行染毒,30d后测定其性腺系数(GSI)和肝指数(LSI),并将鱼体整体匀浆进行常规聚丙烯酰胺凝胶电泳(Native-PAGE)及磷、脂和糖蛋白特异染色分析.结果表明,PCBs对雄性孔雀鱼具有雌激素效应,和E2均可以诱导雄性孔雀鱼体内产生Vtg,但诱导组雄鱼GSI及LSI与对照组比较均无显著性差异(p>0.05).Native-PAGE及磷、脂、糖蛋白特异性分析表明,孔雀鱼Vtg是一种富含磷、脂、糖的蛋白,具有VtgⅠ、VtgⅡ和VtgⅢ等3种形式,其分子量分别为642kDa、541kDa和441kDa.雄性孔雀鱼Vtg可作为环境雌激素监测的有效生物标记物.

Induction and Determination of Vitellogenin in Male Guppies (Poecilia reticulate) after Exposed to Polychlorinated Biphenyls

The effects of 17β-estradiol(E2)and polychlorinated biphenyls(PCBs)on inducing vitellogenin(Vtg)in adult male guppies(Poecilia reticulata)were investigated in order to test if the Vtg could be a valid biomarker for environmental estrogens. Guppies were exposed to E2 and PCBs with 100μg·L-1 and 1500μg·L-1, respectively. After 30 days induction, the gonadosomatic index(GSI)and liver somatic index(LSI) of guppies were measured. Whole body homogenate (WBH) of guppies was carried out by native polyacrylamide gel electrophoresis(Native-PAGE)and staining of gels for phosphorus with methyl green,for lipids with sudan black B,and for carbohydrates with periodic acid-schiff reagent. The results showed that Vtg could be induced from male guppies treated by E2 and PCBs, which indicated that PCBs and E2 possessed estrogenic activity; however, there were no significant differences in GSI or LSI of male fish between treated groups and control groups(p>0.05). The Vtg of guppies was characterized as a phospholipoglycoprotein. Native-PAGE showed that guppies had 3 types of Vtg. Molecular weights for Vtg I, Vtg II and Vtg III were estimated to be 642kDa, 541kDa and 441kDa, respectively. The results indicated that Vtg of the adult male guppies could be a valid biomarker for environmental estrogens.