Korean J Obstet Gynecol.
2002 Oct;45(10):1736-1745.
Regulation of Steroid Thyroid Hormone Receptor 3 (TR3) mRNA Expression by Luteinizing Hormone in Human Early Luteinized Granulosa Cells
- Affiliations
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- 1Department of Obstetrics and Gynecology, Chonnam National University Medical School, Gwang-ju, Korea.
- 2Hormone Research Center, Chonnam National University, Gwang-ju, Korea.
Abstract
OBJECTIVE
The present study examined the gonadotropin regulation of TR3 gene expression by luteinizing hormone (LH) in cultured human luteinized granulosa cells.
METHODS
TR3 mRNA levels were detected by competitive reverse transcriptase-polymerase chain reaction (RT-PCR) method in cultured human luteinized granulosa cells collected from patients undergoing in vitro fertilization.
RESULTS
TR3 transcript was transiently induced by LH, reaching maximum levels 1 hr after stimulation, in a dose-dependent manner. LH-stimulated TR3 expression was abolished by actinomycin D, but was superinduced by cycloheximide. Treatment of luteinized granulosa cells with Rp-cAMP, an inhibitor of protein kinase A, as well as, chelerythrin, an inhibitor of protein kinase C, suppressed LH-stimulated TR3 mRNA levels. In addition, forskolin and TPA mimicked the LH action on the induction of TR3 gene, implying the role of protein kinase A and C activation.
CONCLUSION
Taken together, the present study demonstrates that TR3 gene was rapidly and transiently induced by LH in human luteinized granulosa cells. The results imply that TR3 may play a role in ovulation by initiating a cascade of ovulation-specific gene expression in response to LH.