Effects of 17β-estradiol on Vitellogenin Inducement and Gonad Development in Male Tanichthys albonubes

Vitellogenin （Vtg） was purified from whole body homogenate (WBH) of estradiol-17β (E2) treated male Tanichthys albonubes by gel filtration (Sephacryl S-300). The results showed that the Vtg appeared to exist as homotrimer of approximately 440 kD through native polyacrylamide gel electrophoresis (PAGE). Vtg was characterized as a phospholipoglycoprotein by native-PAGE and staining of gels for CBB R-250, for carbohydrates with periodic acid-schiff reagent, for phosphorus with methyl green and for lipids with sudan black B. Body weight decreased (P<0.01) and the development of sperm was delayed after E2 treatment when compared with the control group of male fish. The results indicated that E2 can induce male fish to produce large quantities of Vtg and have a negative effect on its growth and gonad development. It also indicated that Vtg of the male T. albonubes could be as a valid biomarker for environmental estrogens