Abstract
The rat ovary contains two isozymes of 20α-hydroxysteroid dehydrogenase (HSD-1 and HSD-2). In this study, the expression of activity of each isozyme was investigated in ovaries that contained a single generation of corpora lutea during pseudopregnancy. This condition was induced by cervical stimulation in rats that had been rendered anovulatory by housing them in a continuously lit environment. The total activity of cytosolic 20α-HSD was lower in the ovaries of these pseudopregnant rats than in ovaries containing multiple generations of corpora lutea. In normal pseudopregnancy, HSD-1 activity was low on days 5 and 9 and increased markedly on day 15, whereas HSD-2 was lower than HSD-1 and did not vary throughout pseudopregnancy. However, on days 5 and 9 of continuous-light pseudopregnancy, low activity of HSD-1 only was detected; by day 15, HSD-1 activity had increased sixfold and HSD-2 activity could be detected. Immunohistochemical methods using a specific antibody recognizing both HSD-1 and HSD-2 revealed that the number of 20α-HSD-positive luteal cells increased by day 15. Thus, the increase in total enzyme activity and appearance of HSD-2 activity observed at late pseudopregnancy was accompanied by an increase in the number of 20α-HSD-positive luteal cells.
Original language | English |
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Pages (from-to) | 573-580 |
Number of pages | 8 |
Journal | Journal of Reproduction and Fertility |
Volume | 96 |
Issue number | 2 |
Publication status | Published - 1992 |
Externally published | Yes |
Keywords
- 20α-hydroxysteroid dehydrogenase
- Corpus luteum
- Pseudopregnancy
- Rat
ASJC Scopus subject areas
- Developmental Biology
- Molecular Biology
- Physiology
- Embryology
- Obstetrics and Gynaecology