Mechanisms for Inhibition of Vitellogenin synthesis by Aquatic Pollutants in the Primary Culture of Hepatocytes in Fish

本年度主要研究Al和Cd是否影响雌激素受体（ER）和/或翻译后水平的卵黄蛋白原（VTG）合成。结果是：1。Al和Cd通过影响ER水平抑制VTG合成。然而，这些金属对雌激素（E2）与ER的亲和力没有影响，提示Al和Cd通过E2.2抑制ER本身的表达。Al抑制了肝脏中蛋白激酶C （PKC）的活性，但对VTG的产生没有任何影响。因此，在翻译后水平上，Al通过与PKC无关的过程抑制VTG的产生。环境污染物2,4-二氯苯氧乙酸在肝细胞培养中诱导弱VTG的产生。体内实验显示，Al对金鱼体内VTG合成无影响。应检查铝的浓度依赖性效应。这些结果与去年获得的结果一起表明，Al和Cd在ER和翻译水平上抑制VTG的合成。

In this year, it was mainly examine if Al and Cd affect vitellogenin (VTG) synthesis at estrogen receptor (ER) and/or posttranslational levels. The results are :1. Al and Cd inhibited VTG synthesis by affecting ER levels. However, these metals had no effect on affinity between estrogen (E2) and ER, suggesting that Al and Cd inhibited the expression of ER itself by E2.2. Al inhibited protein kinase C (PKC) activity in the liver without any effects on VTG production. Therefore, Al inhibits VTG production through processes that are unrelated to PKC at a posttranslational level.3. 2,4-Dichlorophenoxyacetic acid, an environmental pollutant, induced weak VTG production in hepatocyte culture.4. An in vivo experiment showed no effect of Al on VTG synthesis in goldfish. Concentration-dependent effects of Al should be examined.These results, together with the results obtained in the last year, show that Al and Cd inhibits VTG synthesis at both ER and translational levels.