[Induction of vitellogenin by estradiol and androgens in a teleostean fish: Gobius niger L].

At any point in the sexual cycle of both males and females, oestradiol benzoate induces synthesis of plasmatic vitellogenin, identifiable by a specific immunserum. Pharmacological doses of purified testosterone and dihydrotestosterone also induce synthesis of this yolk precursor. Although a partial aromatisation of testosterone into oestrogen is possible, our results show that there must also be interaction between the androgens and the oestrogens receptors in the liver.