Gestodene: A novel synthetic progestin — characterization of binding to receptor and serum proteins
| Autor: | K. Schmidt-Gollwitzer, W. Elger, Kunhard Pollow, Sybille Dr. Beier, Bernhard Manz, Hans-Jörg Grill, David Dr Henderson, M. Juchem |
|---|---|
| Rok vydání: | 1989 |
| Předmět: |
Receptors
Steroid medicine.medical_specialty Norpregnenes medicine.drug_class medicine.medical_treatment Estrogen receptor Biology Gestodene Binding Competitive Contraceptives Oral Hormonal Cytosol Glucocorticoid receptor Mineralocorticoids Internal medicine Progesterone receptor medicine Animals Humans Binding site Receptor Progestogen Uterus Obstetrics and Gynecology Rats Inbred Strains Blood Proteins Rats Kinetics Receptors Mineralocorticoid Endocrinology Reproductive Medicine Biochemistry Female Progestins Receptors Progesterone Progestin Protein Binding medicine.drug |
| Zdroj: | Contraception. 40:325-341 |
| ISSN: | 0010-7824 |
| DOI: | 10.1016/0010-7824(89)90096-6 |
| Popis: | Gestodene, 17α-ethinyl-13-ethyl-17β-hydroxy-4,15-gonadien-3-one, is a new orally active progestational agent, which is available for clinical use in oral contraceptives. The aim of the present study is to make a broad characterization of gestodene at the receptor level and to discuss the results in comparison to those of established progestogens. Kinetic studies of H-gestodene uptake show a rapid increase in the amount of specific binding during the first three hours. After saturation, the amount of specifically bound 3 H-gestodege remained almost constant up to 24 hours at 4°C. The dissociation of 3 H-gestodene from the cytoplasmic myometrial progesterone receptor, measured by displacement of labeled steroid with dextran-coated charcoal treatment at 4°C at various times, showed a biphasic or two-component first order dissociation curve. As anticipated, sucrose gradient centrifugation analysis of the 3 H-gestodene-labeled cytosol of human myometrial tissue showed that the gestodene binding components sedimented in the 4S and 8S region. A 200-fold molar excess of nonradioactive gestodene reduced only the 8S binding of 3 H-gestodene. 4S binding of 3 H-gestodene was not reduced, which indicate the existence of a second high capacity binding component. In biological test systems, such as the Clauberg test or Kaufmann test, gestodene has proved to be a very effective progestogen. Among nortestosterone derivatives it is one of the most potent and resembles progesterone biologically in its progestogenic effects. This biologically identical gestagenic activity of gestodene and progesterone is reflected by a very similar behavior in vitro in terms of binding to progesterone receptors of human uterus cytosol. Furthermore, competitive studies indicated that gestodene like other synthetic progestagens also displays some affinity for androgen and glucocorticoid receptors but no measurable affinity for the estrogen receptor. Remarkable is the high binding affinity of gestodene to the binding sites of the mineralocorticoid receptor of rat kidney with a RBA value of 350% compared to aldosterone. In contrast to progesterone, gestodene did not bind to CBG, but was bound with a relatively high affinity for SHBG, which is a typical behavior for all 19-nortestosterone derivatives. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|