HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 68/6/2180    most recent biolreprod.102.013011v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal My Folders Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Roy, S. K. Articles by Yang, P. Search for Related Content PubMed PubMed Citation Articles by Roy, S. K. Articles by Yang, P. Agricola Articles by Roy, S. K. Articles by Yang, P.

Dexamethasone Inhibits Transforming Growth Factor-ß Receptor (TßR) Messenger RNA Expression in Hamster Preantral Follicles: Possible Association with NF-YA¹

Departments of Obstetrics and Gynecology and Physiology and Biophysics, University of Nebraska Medical Center, Omaha, Nebraska 68198-4515

To evaluate the site(s) and mechanism(s) of glucocorticoid-inhibition of transforming growth factor (TGF) ß receptor (TßR) mRNA expression in ovarian cells, steady-state levels of TßR mRNA in hamster preantral follicles exposed to FSH or estradiol with or without dexamethasone were determined by reverse transcription polymerase chain reaction and Southern hybridization. The effect of dexamethasone on follicular DNA and steroid synthesis and the expression of NF-Y and Sp3 were also investigated. Dexamethasone differentially inhibited FSH- or estradiol-induced expression of TßR mRNA in preantral follicles at all stages. Dexamethasone also strongly inhibited FSH-induced but not TGFß2-induced follicular DNA synthesis, and the inhibition was completely reversed by TGFß2. However, TGFß2 markedly attenuated FSH + dexamethasone-stimulated progesterone and FSH-induced follicular estradiol synthesis. Both FSH and estradiol upregulated NF-YA expression, but the effect was significantly attenuated by dexamethasone. Our results suggest that suppression of NF-YA levels is one of the mechanisms whereby dexamethasone reduces hormone-induced TßRI and TßRII mRNA levels in hamster preantral follicles. Dexamethasone potentiates the effect of FSH on granulosa cell steroidogenesis, whereas TGFß counteracts the effect. These data indicate that glucocorticoid and TGFß may form an important regulatory loop to modulate FSH regulation of preantral follicular growth and differentiation.

¹ This study was supported by research grants HD 28165 and HD 38468 from the National Institute of Child Health and Human Development, NIH.

² Correspondence: Shyamal K. Roy, Departments of Obstetrics and Gynecology and Physiology and Biophysics, BH 4030, University of Nebraska Medical Center, 984515 Nebraska Medical Center, Omaha, NE 68198-4515. FAX: 402 559 6164; skroy{at}unmc.edu

This article has been cited by other articles:

				A. Elnashar, E. Abdelmageed, M. Fayed, and M. Sharaf Clomiphene citrate and dexamethazone in treatment of clomiphene citrate-resistant polycystic ovary syndrome: a prospective placebo-controlled study Hum. Reprod., July 1, 2006; 21(7): 1805 - 1808. [Abstract] [Full Text] [PDF]

				P. Yang and S. K. Roy Follicle Stimulating Hormone-Induced DNA Synthesis in the Granulosa Cells of Hamster Preantral Follicles Involves Activation of Cyclin-Dependent Kinase-4 Rather Than Cyclin D2 Synthesis Biol Reprod, February 1, 2004; 70(2): 509 - 517. [Abstract] [Full Text] [PDF]