Progesterone Metabolism by the Ovary of the Pregnant Rat: Discrepancies in the Catabolic Regulation Model112
| Autor: | Joanne S. Richards, M. Margaret Knudson, A. Rees Midgley, Laura R. Lacy, Julie J. Williams |
|---|---|
| Rok vydání: | 1976 |
| Předmět: | |
| Zdroj: | Endocrinology. 99:929-934 |
| ISSN: | 1945-7170 0013-7227 |
| DOI: | 10.1210/endo-99-4-929 |
| Popis: | The intraovarian site of 20α-hydroxysteroid dehydrogenase activity (20α-OH-SDH) was determined biochemically by measuring enzyme activity in homogenates of the whole ovary, or of isolated ovarian compartments, during the last third segment of pregnancy in the rat. In agreement with previously reported histochemical evidence, an increase in 20α-OH-SDH activity was observed in isolated corpora lutea, but not in the non-luteal compartment of the ovary. Enzyme activity in corpora lutea was low between days 16 and 22 of pregnancy, but increased markedly (4–6 fold) on day 23. Between days 17 and 20 of pregnancy, serum concentrations of progesterone declined from 130 ±3 to 80 ± 3 ng/ml, while 20α-hydroxypregn-4- en-3-one (20α-OH-P) concentrations declined from 34 ± 3 to 18.5 ± 3 ng/ml. Only later, between days 20 and 22 of pregnancy, was a significant decline in serum progesterone concentrations associated with an increase in serum 20α-OH-P concentrations (50 ± 15 ng/ml at 0800 h and 128.5 ± 15 ng/ml at 1400 h o... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|