Effects Of Nonylphenol On Estrogen Receptor And Vitellogenin In Rana Liver Cells

With the rapid development of modern industry, a large number of chemical substances used in the environment have caused serious pollution to the survival of wild animals. Among them, phenolic environmental pollutants as endocrine disruptors have seriously affected the growth of animals and caused animal populations decline. Nonylphenol(Nonylphenol,NP) is one of endocrine disrupting chemicals, which has similar structure to animal estrogen, with weak estrogenic effects. In this experiment, male Rana chensinensisas as the experimental animals were used to investigate effects of NP on hepatic cells of estrogen receptor (ER) and vitellogenin (Vtg) expression, which can deeply reveal the estrogenic effects of NP and the impact of phenolic environmental chemical pollutants on amphibian endocrine system, so as to provide a theoretical basis.at amphibian decline in reproductive capacity caused by NP pollution.In this study, male Rana chensinensisas were treated in 10-5,10-6,10-7 M NP water for 10d,20d,30d,10-8,10-9 M 17(3-estradiol (17β-estradiol, E2) as a 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 Vtg show that the positive effect of Vtg is brown or yellow in the cytoplasm. The results of the relative intensity of Vtg show that in addition to the 10-(?)M NP treatment group in lOd was not significant (P>0.05), the remaining NP treatment groups were significantly higher(P<0.05). the 10-5,10-6 M NP treatment groups were significant different (P＜0.05), in the 20d and 30d, Vtg expression increase was significantly different (P＜0.01). The expression of Vtg in NP treated group is less than E2 treated group. The expression of Vtg and NP is the dose-time-response relationship, which is similar to the effects of E2 treatment groups.2. The results of immunohistochemical technique of ER show that the positive effect of ER is brown or yellow in the nuclear and cytoplasm. The results of the relative intensity of ER show that the expression of ER increased significantly in hepatic cells of R.chensinensis in NP treated groups compared with the control group. And the expression of ER in NP treated group is significantly lower than the E2 treated group. The 10-5,10-6 and 10-7M NP treatment groups were significant different(P<0.05). in the 30d, ER expression increase was significantly different(P<0.01).In NP treated groups, the expression of ER is increased with the increasing concentration of NP or with the increasing treated time. In E2 treated group, the expression of ER is changed in a similar trend.3.The results of in situ hybridization detection of ER mRNA show that the positive effect of ER mRNA is blue in the cytoplasm in NP treated groups and E2 treated group. The 10-5,10-6 and 10-7M NP treatment groups were significant different(P<0.05), in the 20d and 30d, ER mRNA expression increase was significantly different(P<0.01).In each NP group, the expression of ER mRNA is significant increased with the increasing treated time and the increasing treated concentration. These can be seen the change of ER mRNA expression in hepatic cells is consistent with ER mRNA with a high-profile trend in the NP and E2 treatment, which was indicated that the synthesis process of ER was along with ER mRNA expression.4. The relationship between ER and Vtg in hepatic cells of R. chensinensis treated by NP shown that NP can induce the increasing expression of ER and Vtg and the change trend is the same. It's illuminated that the expression of ER along with the synthesis of Vtg, and NP induces the synthesis of Vtg protein through with the effect way of ER.5. This experiment use E2 as positive control. NP and E2 have the similar effect. But the lowest concentration of NP is higher than the highest concentration of E2, which indicated that the estrogenic effect of NP is lower than the effects of E2, the results showed that NP can play weak estrogenic effects.The results showed that NP can affect the expression of ER and Vtg in hepatic cells of R. chensinensis, NP can induce the synthesis of Vtg though ER and plays weak estrogenic effects.