Validation of an enzyme-linked immunosorbent assay for measuring vitellogenin in California halibut (Paralichthys californicus).

Vitellogenin (VTG) is the major protein present in the plasma of females undergoing oogenesis. In males, the VTG gene normally is suppressed; however, synthesis of VTG can be induced by exposure to xenoestrogenic compounds. In the present study, an enzyme-linked immunosorbent assay was developed and validated to evaluate VTG levels in the California halibut (Paralichthys californicus). Vitellogenin and lipovitellin (LV) were identified in the plasma of 17 beta-estradiol-induced females and in the ovaries of wild females, to our knowledge for the first time. Purified VTG from the plasma of induced females was obtained, and polyclonal antibodies against the LV of mature female ovaries was prepared and their specificity assessed by Western blot analysis. At Bahía Magdalena, Baja California Sur, México, quantitative measurements of VTG in the plasma of female specimens were made during one reproductive cycle.