These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Characterization of gonadotropin-releasing hormone receptors in goldfish ovary: variation during follicular development.
    Author: Pati D, Habibi HR.
    Journal: Am J Physiol; 1993 Feb; 264(2 Pt 2):R227-34. PubMed ID: 8383461.
    Abstract:
    Gonadotropin-releasing hormone (GnRH) receptors were characterized in the goldfish ovary using an analogue of salmon GnRH ([D-Arg6,Trp7,Leu8,Pro9-NEt]GnRH; sGn-RH-A) as a labeled ligand. Binding of sGnRH-A to goldfish follicular membrane preparation was found to be saturable, reversible, and dependent on time, temperature, tissue concentration, and pH. Addition of unlabeled sGnRH-A displaced the bound 125I-labeled sGnRH-A in a dose-related manner. Hill plot as well as Scatchard analysis indicated the presence of two classes of binding sites, a high-affinity/low-capacity site and a low-affinity/high-capacity site, in the fully mature and less mature goldfish ovary. However, immature goldfish ovary contained only a single class of low-affinity binding sites. The equilibrium association constants (Ka) of the low-affinity sites were found to be similar in all follicular groups. However, there was a tendency for a higher Ka value of the high-affinity sites in the less mature follicles (0.5-0.95 mm) compared with the fully mature follicles (1.11-1.48 mm), although the differences were not statistically significant. Bound 125I-sGnRH-A was also found to be displaceable by sGnRH ([Trp7,Leu8]GnRH) and chicken GnRH-II (cGnRH-II; [His5,Trp7,Tyr8]GnRH), which occur naturally in the goldfish brain. sGnRH-A and cGnRH-II were found to bind with greater affinity than sGnRH to the goldfish ovarian GnRH binding sites.
    [Abstract] [Full Text] [Related] [New Search]