All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

  • Blackwell Publishing Ltd  (1)
  • 2000-2004
  • 1995-1999  (1)
  • 1
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Exposure of sea bass Dicentrarchus labrax oocytes to 25, 50, 100, and 300 IU ml−1 of human chorionic gonadotropin (hCG) resulted in a dose-dependent increase (ED50=60 IU ml−1) in the maximal maturation and volume response rate over a 120-h incubation period. Oocytes responded in a similar dose-dependent manner to graded doses of homologous sea bass pituitary extract (ED50=3·3#10−2 PE ml−1). The response latency of sea bass oocytes to endogenous and exogenous gonadotropins was similar (t1/2≃45 and 48 h, respectively). Both 17α,20β-dihydroxy-4-pregnen-3-one (17,20βP) and 17α,20β,21-trihydroxy-4-pregnen-3-one (20βS) stimulated maturation in a dose- and time-dependent manner with t1/2 values less than those of hCG (15 h and 7·5 h at 100 ng ml−1, respectively); 17α,20α-dehydroxy-4-pregnen-3-one (17,20αP) was ineffective. 17,20βP was more potent at all doses tested. The stimulatory actions of gonadotropin and maturation-inducing steroid (MIS) involved both transcription and translation since maturation was significantly inhibited in the presence of actinomycin D and cycloheximide. Moreover, pituitary extract and hCG stimulated release of higher levels of 17,20βP in a dose- and time-dependent manner in follicle incubations as compared to 20βS suggesting that this steroid may in fact be the MIS in this species.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...