Expression and functional characterization of intrafollicular GH-IGF system in the XXXX ovary.

@entity37651 @entity22820 @entity22822 @entity3392 @entity37650 @entity22821 @entity10759 @entity22819
UNASSIGNED: The @entity10759 plays important roles in influencing reproduction. All key members of this axis including growth hormone (GH, gh), GH receptors (ghra and ghrb), insulin-like growth factors (IGFs, @entity22819 , @entity22820 and @entity22821 ) and IGF receptors ( @entity37650 and @entity37651 ) were detected in the @entity3392 ovary. GH was exclusively expressed in the full-grown oocytes, while its receptors were detectable in both the follicle cells and oocytes. The IGFs and their receptors were all expressed in both compartments except @entity22821 , which was expressed in the follicle cells only. During folliculogenesis, there was a sharp decrease of gh expression at follicle activation; however, the expression of its receptors increased significantly. The expression profiles of @entity22819 , @entity22820 , and @entity22822 were similar to that of fshr, whereas @entity22821 expression was close to lhcgr, suggesting differential roles for different forms of IGFs in follicle development. To examine if the ovarian GH-IGF system is regulated by gonadotropins (e.g., hCG) and GH, we performed in vitro experiments using cultured @entity3392 follicle cells. The expression of @entity22819 and @entity37650 , but not others, was down-regulated by hCG (LH analog), whereas recombinant @entity3392 GH stimulated @entity22819 expression. In addition, GH also increased the expression of activin bA subunit (inhbaa). In agreement with this, the stimulatory effect of GH but not @entity22819 on oocyte maturation could be abolished by follistatin. In conclusion, the present study revealed an intrafollicular network involving GH-IGF mini-axis in the @entity3392 ovary; however, it might not work in the same way as that of the systemic @entity10759 .
