Effects of Gonadotropin-Releasing Hormone Agonist on Steroidogenesis in the Rat Ovary
| Autor: | Shoichi Okinaga, Naofumi Yago, Satoko Arakawa, Hiroyuki Mori, Tomi Ohkawa, Shin-ichi Takada, Tetsuo Morita |
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| Rok vydání: | 1994 |
| Předmět: |
endocrine system
medicine.medical_specialty medicine.drug_class Endocrinology Diabetes and Metabolism Ovary Buserelin Chorionic Gonadotropin Human chorionic gonadotropin Follicle Aromatase Endocrinology Internal medicine Gonadotropin-releasing hormone agonist Luteolysis medicine Animals Rats Wistar Diethylstilbestrol Cells Cultured Progesterone Hypophysectomy Estradiol Chemistry Rats Kinetics medicine.anatomical_structure Female Follicle Stimulating Hormone Gonadotropin Receptors LHRH hormones hormone substitutes and hormone antagonists Hormone medicine.drug |
| Zdroj: | Hormone Research. 41:14-21 |
| ISSN: | 1423-0046 0301-0163 |
| DOI: | 10.1159/000183938 |
| Popis: | To assess the regulatory roles of gonadotropin-releasing hormone (GnRH) in ovarian function, the kinetics of the ovarian GnRH receptor and the effects of the GnRH superagonist buserelin on steroidogenesis in ovarian cell culture were examined. Scatchard analysis of buserelin-binding to crude ovarian cell membrane revealed a specific high-affinity GnRH receptor. Buserelin together with follicle-stimulating hormone stimulated estradiol (E2) production in immature follicles in hypophysectomized and DES-treated rats. On the other hand, applied to developing follicles of rats treated with pregnant-mare-serum gonadotropin buserelin suppressed E2 production to terminate follicle maturation and simultaneously stimulated progesterone (P4) production to induce luteinization. With ovarian cells luteinized by human chorionic gonadotropin in vitro, buserelin suppressed production of both P4 and E2, leading to luteolysis. Buserelin affected steroid production by modulating activities of key enzymes in steroid synthesis. These findings indicate that buserelin action depended on the gonadotropin priming of ovarian cells, and suggest the possible involvement of GnRH in the regulation of steroidogenesis throughout the ovulatory cycle. |
| Databáze: | OpenAIRE |
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