Endocrinology, Vol 136, 974-980, Copyright © 1995 by Endocrine Society

ARTICLES

Homologous and heterologous regulation of gonadotropin-releasing hormone receptor gene expression in preovulatory rat granulosa cells

JI Olofsson, CC Conti and PC Leung
Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, Canada.

The reverse transcription-polymerase chain reaction was used to evaluate the influence of gonadotropins and GnRH on GnRH receptor gene expression in cultured preovulatory rat granulosa cells. Cells were obtained from immature female rats 48 h after priming with 10 IU PMSG, sc, and cultured in medium containing LH, FSH, or GnRH after a 24-h preincubation period. After culture, cells were lysed, total RNA was extracted, and culture medium was assayed for its content of progesterone, and estradiol by RIA. Subsequent to reverse transcription, complementary DNA was subjected to polymerase chain reaction, after which the products formed were transferred to nylon filters and hybridized with a 416-basepair internal rat GnRH receptor complementary DNA probe. As an amplification control, Southern hybridization of glyceraldehyde-3-phosphate dehydrogenase messenger RNA (mRNA) was performed. Treatment with LH increased both progesterone and estradiol output, whereas GnRH receptor mRNA levels were markedly suppressed in a dose-related fashion, with maximal inhibition seen at 100-1000 ng (P < 0.05). In contrast, FSH in concentrations between 1- 1000 ng was without effect on GnRH receptor gene expression. Time- course analysis revealed that GnRH receptor gene expression was not affected by LH (1000 ng) until 12 h, when transcript levels fell to 24% of those seen at 0 h (P < 0.05). This pronounced decrease in GnRH receptor mRNA abundance is, however, transient, because after 48 h, levels returned to those seen before LH treatment. As GnRH has been postulated to directly influence its own receptor synthesis in the pituitary, the effect of GnRH treatment of granulosa cells during a 24- h culture period was also evaluated. In GnRH-treated cells, a dose- dependent increase in GnRH receptor mRNA levels was seen, with maximal effects (2.4-fold; P < 0.05) at 10(-6) M. The demonstration of agonist- specific up- and down-regulation of GnRH receptor gene expression in preovulatory granulosa cells adds further support to the extrapituitary actions of GnRH as an important autocrine/paracrine factor involved in the regulatory events during the periovulatory period.

This article has been cited by other articles:

				K. Walters, I. N. Wegorzewska, Y.-P. Chin, M. G. Parikh, and T. J. Wu Luteinizing Hormone-Releasing Hormone I (LHRH-I) and Its Metabolite in Peripheral Tissues Experimental Biology and Medicine, February 1, 2008; 233(2): 123 - 130. [Abstract] [Full Text] [PDF]

				C. Metallinou, B. Asimakopoulos, A. Schroer, and N. Nikolettos Gonadotropin-Releasing Hormone in the Ovary Reproductive Sciences, December 1, 2007; 14(8): 737 - 749. [Abstract] [PDF]

				J.-H. Choi, C. B. Gilks, N. Auersperg, and P. C. K. Leung Immunolocalization of Gonadotropin-Releasing Hormone (GnRH)-I, GnRH-II, and Type I GnRH Receptor during Follicular Development in the Human Ovary J. Clin. Endocrinol. Metab., November 1, 2006; 91(11): 4562 - 4570. [Abstract] [Full Text] [PDF]

				J.-H. Choi, K.-C. Choi, N. Auersperg, and P. C K Leung Differential regulation of two forms of gonadotropin-releasing hormone messenger ribonucleic acid by gonadotropins in human immortalized ovarian surface epithelium and ovarian cancer cells. Endocr. Relat. Cancer, June 1, 2006; 13(2): 641 - 651. [Abstract] [Full Text] [PDF]

				C. K. Cheng and P. C. K. Leung Molecular Biology of Gonadotropin-Releasing Hormone (GnRH)-I, GnRH-II, and Their Receptors in Humans Endocr. Rev., April 1, 2005; 26(2): 283 - 306. [Abstract] [Full Text] [PDF]

				F. Parborell, G. Irusta, A. Vitale, O. Gonzalez, A. Pecci, and M. Tesone Gonadotropin-Releasing Hormone Antagonist Antide Inhibits Apoptosis of Preovulatory Follicle Cells in Rat Ovary Biol Reprod, March 1, 2005; 72(3): 659 - 666. [Abstract] [Full Text] [PDF]

				A. Chamson-Reig, E. M. Sorianello, P. N. Catalano, M. O. Fernandez, O. P. Pignataro, C. Libertun, and V. A. R. Lux-Lantos Gonadotropin-Releasing Hormone Signaling Pathways in an Experimental Ovarian Tumor Endocrinology, July 1, 2003; 144(7): 2957 - 2966. [Abstract] [Full Text] [PDF]

				J.-Y. Park, J.-H. Park, H.-J. Park, J.-Y. Lee, Y.-I. Lee, K. Lee, and S.-Y. Chun Stage-Dependent Regulation of Ovarian Pituitary Adenylate Cyclase-Activating Polypeptide mRNA Levels by GnRH in Cultured Rat Granulosa Cells Endocrinology, September 1, 2001; 142(9): 3828 - 3835. [Abstract] [Full Text] [PDF]

				S. K. Kang, C.-J. Tai, P. S. Nathwani, K.-C. Choi, and P. C. K. Leung Stimulation of Mitogen-Activated Protein Kinase by Gonadotropin-Releasing Hormone in Human Granulosa-Luteal Cells Endocrinology, February 1, 2001; 142(2): 671 - 679. [Abstract] [Full Text] [PDF]

				S. K. Kang, C.-J. Tai, P. S. Nathwani, and P. C. K. Leung Differential Regulation of Two Forms of Gonadotropin-Releasing Hormone Messenger Ribonucleic Acid in Human Granulosa-Luteal Cells Endocrinology, January 1, 2001; 142(1): 182 - 192. [Abstract] [Full Text] [PDF]

				J. Dor, D. Bider, A. Shulman, J. Levron, S. Shine, S. Mashiach, and J. Rabinovici Effects of gonadotrophin-releasing hormone agonists on human ovarian steroid secretion in vivo and in vitro--results of a prospective, randomized in-vitro fertilization study Hum. Reprod., June 1, 2000; 15(6): 1225 - 1230. [Abstract] [Full Text] [PDF]

				P. S. Nathwani, S. K. Kang, K. W. Cheng, K.-C. Choi, and P. C. K. Leung Regulation of Gonadotropin-Releasing Hormone and Its Receptor Gene Expression by 17{beta}-Estradiol in Cultured Human Granulosa-Luteal Cells Endocrinology, May 1, 2000; 141(5): 1754 - 1763. [Abstract] [Full Text] [PDF]

				A. Chamson-Reig, O. P. Pignataro, C. Libertun, and V. A. R. Lux-Lantos Alterations in Intracellular Messengers Mobilized by Gonadotropin-Releasing Hormone in an Experimental Ovarian Tumor Endocrinology, August 1, 1999; 140(8): 3573 - 3580. [Abstract] [Full Text]

				U. Ottander, C. H.B. Leung, and J. I. Olofsson Functional evidence for divergent receptor activation mechanisms of luteotrophic and luteolytic events in the human corpus luteum Mol. Hum. Reprod., May 1, 1999; 5(5): 391 - 395. [Abstract] [Full Text] [PDF]

				H.-F. Chen, E.-B. Jeung, M. Stephenson, and P. C. K. Leung Human Peripheral Blood Mononuclear Cells Express Gonadotropin-Releasing Hormone (GnRH), GnRH Receptor, and Interleukin-2 Receptor {gamma}-Chain Messenger Ribonucleic Acids That Are Regulated by GnRH in Vitro J. Clin. Endocrinol. Metab., February 1, 1999; 84(2): 743 - 750. [Abstract] [Full Text]