17β-雌二醇对雄性瓦氏黄颡鱼(Pelteobagrus vachelli)的雌激素效应

ESTROGENIC EFFECT OF 17β-ESTRADIOL ON MALE BAGRID CATFISH PELTEOBAGRUS VACHELLI

以三峡库区小型经济鱼类瓦氏黄颡鱼雄鱼为对象,研究17β-雌二醇对它的雌激素效应。在不同的温度和剂量条件下测定血清卵黄蛋白原、Ca2+、总磷、无机磷的含量,以及肝胰脏RNA/DNA比率。结果表明,与对照组相比,当水温≥16℃、剂量≥1.0μg/g,以及水温≥19℃、剂量≥0.1μg/g条件下,17β-雌二醇可诱导雄性瓦氏黄颡鱼产生卵黄蛋白原,而且其水平增加呈明显的剂量依赖;当水温≥16℃、剂量≥1.0μg/g时,血清Ca2+含量极显著增加,呈明显的剂量依赖;试验组血清各种磷组分增加也呈剂量依赖;17β-雌二醇也引起肝胰脏代谢指标RNA/DNA比率增加。结果表明,雄性瓦氏黄颡对雌激素有较高的敏感性,加上其体型适中,容易获得等特性,可以作为水环境雌激素内分泌干扰物检测的指示生物。血清卵黄蛋白原与Ca2+可以作为污染水体雌激素内分泌干扰物的检测指标。

The present study investigates the estrogenic effects of 17β-estradiol as endocrinal disrupting chemicals on male bagrid catfish Pelteobagrus vachelli, the major commercial fish in the Three Gorges Reservoir area, China. At different temperatures and doses, the serum vitellogenin, calcium ion, phosphorous components, and RNA/DNA ratios in liver are determined. The results indicate that, comparing to the control at water temperature≥ 16℃, 17β-estradiol dose ≥ 1.0μg/g, or≥ 19℃, dose≥0.1μg/g, vitellogenin was induced by 17β-estradiol injection in male fish, which is obviously dose- and temperature-dependent. At water temperature ≥ 16℃ and dose ≥1.0 μg/g, the serum calcium ion level increased significantly, being obviously dose- and temperature-dependent. Similar results are observed with several serum phosphorous components in fish from the same groups. The RNA/DNA ratios in hepatopancreatic tissue increased after 17 β -estradiol treatment. The results reveal that male P. vachelli is highly sensitive to estrogens. In addition to the moderate size, the availability, and the simplicity in raising and sampling procedures in laboratory, it can be used as a biomarker organism for measuring environmental estrogenic endocrine disorder. The serum vitellogenin and calcium ion in male P. vachelli are suitable biomarkers indicative of endocrine disruption in polluted water.