Sex hormone-binding globulin stimulates chorionic gonadotrophin secretion from human cytotrophoblasts in culture
| Autor: | C Arranz, M Deas, G Queipo, Fernando Larrea, R González, C Cariño |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
endocrine system
medicine.medical_specialty medicine.drug_class 8-Bromo Cyclic Adenosine Monophosphate Biology Chorionic Gonadotropin Culture Media Serum-Free Syncytiotrophoblast Sex hormone-binding globulin Cell surface receptor Pregnancy Internal medicine Culture Techniques Sex Hormone-Binding Globulin polycyclic compounds medicine Cyclic AMP Humans Receptor reproductive and urinary physiology Testosterone Estradiol Rehabilitation Obstetrics and Gynecology Dihydrotestosterone Trophoblasts Endocrinology medicine.anatomical_structure Reproductive Medicine biology.protein Female Cytotrophoblasts Gonadotropin hormones hormone substitutes and hormone antagonists medicine.drug |
| Zdroj: | Human reproduction (Oxford, England). 13(5) |
| ISSN: | 0268-1161 |
| Popis: | The effects of sex hormone-binding globulin (SHBG) on the secretion of human chorionic gonadotrophin (HCG) and cAMP by cultured human cytotrophoblasts were investigated. Cytotrophoblasts obtained from normal term placentae were cultured in serum-free medium with or without the addition of human SHBG. The presence of SHBG in the medium increased the release of HCG and the accumulation of cAMP. Ligand-free SHBG was able to raise both HCG and cAMP concentrations and the maximal response was observed with 1 nM of the steroid-binding globulin. Addition of either oestradiol or 5alpha-dihydro-testosterone (DHT) to cultures previously incubated with SHBG in a final molar ratio of 1:10 resulted in a further increase of HCG and cAMP concentrations. This effect was blocked when cultured placental cells were exposed to SHBG that was previously saturated with DHT or when incubated in the presence of steroids only. The results of the present study provide evidence for the in-vitro regulation of HCG secretion by SHBG and further support the concept that this steroid-binding protein may act as a mediator of steroid action at the cellular level. Finally, the increase in cAMP suggests that SHBG receptor located in the surface of syncytiotrophoblast membranes is coupled to adenylate cyclase as part of the G-protein receptor family. Our results may provide new insights into the biological implications of extracellular steroid-binding proteins as well as new perspectives on the endocrinology of pregnancy. |
| Databáze: | OpenAIRE |
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