Bpa Male Chinese Rana (rana Chensinensis) Liver Cells, The Estrogen Receptor And Vitellogenin

In recent years, with the rapid development of industry and agriculture, a large number of compounds are continuously released into the environment. They can disturb the environment and the healthy of human. More and more evidences that many chemical pollutants in the environment can interfere with wild animals and human activities in the normal physiology were shown. Studies have shown that bisphenol A (BPA) as environmental estrogens can affect the growth of amphibian development and reproduction. Polyphenols can also induce estrogen receptor (ER) or vitellogenin (VTG) in other animal cells. Little studies show that BPA induce the synthesis of ER and VTG, and their relationship in hepatic cells of amphibians. In this experiment, we use male Rana chensinensis as laboratory animals to explore the effects of ER and VTG in hepatic cells by BPA, We will reveal the mechanism of phenols chemical, in order to understand the estrogenic effects of BPA, to investigate the relationship between estrogen receptor and vitellogenin, to provide a theoretical basis in order to clarify the molecular mechanism of BPA.We take male R. chensinensis as experiment animals. Animals had been treated in 10^-7, 10^-6, and 10^-5mol/L BPA for 10d, 20d, and 30d. 17β-estradiol (E₂) as positive control, then liver tissue was got from R.chensinensis at certain days. Hepatic cells are detected the expression of protein of ER and VTG by immunohistochemical technique, and the expression of ER mRNA by in situ hybridization technique .The results and conclusions of experiment as follows:1. The results of immunohistochemical technique of ER show that ER expresses in the BPA and E₂ treated group. The positive effects of ER is yellow or brownish yellow in nucleus, and flake in cytoplasm. The results of the relative intensity of estrogen receptor show that the expression of ER increased significantly in hepatic cells of R.chensinensis in BPA treated group compared with the control group. And the expression of ER in BPA treated group is significantly lower than the E₂ treated group. In BPA treated group, the expression of ER is increased with the increasing concentration of BPA, or with the increasing treated time. In E₂ treated group, the expression of ER is change in a similar trend.The results of in situ hybridization detection of ER mRNA show that there are positive nuclear particles in hepatic cells in BPA treated groups and E₂ treated group. The positive effects is blue in nuclear, and ring or semi-ring in the nuclear membrane, and flake in cytoplasm. In addition to BPA 10^-7 mol/L treated group, the expression of ER mRNA in each group is significantly higher than the control group. In each group, the expression of ER mRNA is significant increased with the increasing treated time and the increasing treated concentration. But in BPA10^-5 and BPA10^-6 mol / L treatment group, the difference of the expression of ER mRNA isn't significant.At the same treated time, the expression of ER mRNA is relevant to the synthesis of ER protein induced by BPA. It's illustrated that BPA have the dose-response effect and can accumulate in hepatic cells of Rana chensinensis. The effect of BPA is similar to the effect of E₂ that can explain that the way of the expression of ER induced by BPA and E₂ is similar. However, the increasing synthesis of ER protein lags behind the increasing expression of ER mRNA, the expression of ER mRNA induced by BPA or E₂ changed significantly in a short time, but the synthesis of protein is a long process.2. The results of immunohistochemical technique of VTG show that VTG express in the BPA and E₂ treated group. The positive effect of VTG is yellow or brown in the cytoplasm. The results of the relative intensity of VTG show that the expression of VTG increased significantly in hepatic cells of R.chensinensis in BPA treated group compared with the control group. The expression of VTG in BPA treated group is less than E₂ treated group. In BPA treated group, the expression of VTG is increased with the increasing treated time and increase BPA. The expression of VTG and BPA is the dose-time-response relationship. In E₂ treated group, the expression of ER is change in a similar trend. The level of VTG in hepatic cells of R.chensinensis induced by BPA10^-5mol/L has the trend of reduce, that may be due to hepatic cells beginning to necrosis caused by BPA10^-5mol/L treatment group.3. The relationship between ER and VTG in hepatic cells of R. chensinensis treated by BPA shown that BPA can induce the increasing expression of ER and VTG, the change trend is same. It's illuminate that the expression of ER along with the synthesis of VTG, BPA induces the synthesis of VTG protein through with the effect way of ER.4. This experiment use E₂ as positive control, the change trend of ER and VTG induced by BPA and E₂. BPA and E₂ have the similar effect. But the lowest concentration of BPA is higher than the highest concentration of E₂, which indicated that the estrogenic effect of E₂ is higher than the effects of BPA.The results showed that BPA can affect the expression of ER and VTG in hepatic cells of R. chensinensis, BPA can induce the synthesis of VTG though ER.