Effects of insulin-like growth factor I (IGF-I) on steroid production by isolated ovarian theca and granulosa layers of preovulatory coho salmon
Maestro, M.A.; Planas, J.V.; Gutiérrez, J.; Moriyama, S.; Swanson, P. (1995). Effects of insulin-like growth factor I (IGF-I) on steroid production by isolated ovarian theca and granulosa layers of preovulatory coho salmon. Neth. J. Zool. 45(1-2): 143-146
In: Netherlands Journal of Zoology. E.J. Brill: Leiden. ISSN 0028-2960; e-ISSN 1568-542X, more
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Authors | | Top |
- Maestro, M.A.
- Planas, J.V.
- Gutiérrez, J.
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Abstract |
The effects of recombinant human and salmon insulin-like growth factor-I (IGF-I) on in vitro steroid production by isolated theca and granulosa cell-layers of the preovulatory coho salmon ovary were examined. Prior to germinal vesicle breakdown (GVDB), IGF-I decreased basal theca cell-layer production of testosterone (T) and 17 alfa-hydroxyprogestrone (17-OHP) and also inhibited the stimulatory effects of gonadotropin II (GTH II) on T production. After GVBD, IGF-I lowered the GTH II-induced production of both steroids by theca cells. In contrast, IGF-I enhanced the stimulatory efects of GTH II on conversion of 17 OH-P to 17 alfa, 20 bèta-dihydroxi-4-pregnen-3-one (17, 20 bèta P) by granulosa cells during final oocyte maturation. |
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