Estrogen levels in the gonads of marine bivalves, the Pacific oyster Crassostrea gigas and scallop Patinopecten yessoensis were determined by high performance liquid chromatography (HPLC) using an electrochemical detector. Estrone (E1), estradiol-17β (E2), and a small amount of estriol (E3) were identified in the ovary, while only E2 was found in the testis. The level of E2 in the ovary was consistently higher than E1 and it increased with sexual maturation. These results indicate that E2 may play a role in the reproductive events of the oyster and scallop. In vitro experiments demonstrated the presence of 17β-hydroxysteroid dehydrogenase (17β-HSD) in the ovaries of both bivalves. The activity of 17β-HSD in the ovary was lower in the postspawning stage than in the early differentiating stage. The evidence for the presence of aromatase activity in the scallop ovary was obtained by 3H-water assay. The immunoreactivity against 3β-hydroxysteroid dehydrogenase (3βHSD), P450 aromatase and E2 was detected in the cells along the outside of germinal acini of the scallop ovary. It is concluded that estrogens can be synthesized in the gonad, that their levels vary with the reproductive cycle, and that they have a role in the development of gametes.
|ジャーナル||Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology|
|出版ステータス||Published - 1997|
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