INDUCTION OF VITELLOGENIN SYNTHESIS IN GOLDFISH BY MASSIVE DOSES OF ANDROGENS

Oral administration of massive doses of methyltestosterone into goldfish caused an extensive proliferation of the rough endoplasmic reticulum, hypertrophy of the Golgi apparatus, and the production of numerous secretory granules in the liver, suggesting the induced synthesis of some secretory proteins. The electrophoretic pattern of serum proteins was prominently altered, showing three bands which were absent in normal, immature fish. All of these changes were similarly observed in estradiol-treated fish. In order to identify the hormone-induced serum proteins, they were purified from estradiol- and methyltestosterone-treated fish and were subjected to chemical and immunological analyses. The results indicated that the serum proteins induced by methyltestosterone and by estradiol are identical in the contents of lipids, phospholipids, calcium, and protein-bound phosphorus and the reactivity to antiserum elicited to the estradiol-induced serum proteins. Furthermore, it was found that the antibody forms a single, connecting precipitin line with the hormone-induced proteins, sera of vitellogenic fish, and ovary extracts of matured fish, but not with sera of normal males. In view of the above findings, it was concluded that the serum proteins induced by methyltestosterone are vitellogenin. Ethynyltestosterone and methylandrostenediol were also effective, but testosterone, dihydrotestosterone, and methyldihydrotestosterone were much less effective in inducing vitellogenin synthesis. © 1979.