• 대한수의학회지
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• 제34권4호
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• pp.867-872
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• 1994

Progesterone catabolizing enzyme, the enzyme $20{\alpha}$-hydroxysteroid dehydrgenase($20{\alpha}$-HSD) is pivotal in the regulation of ovarian function in rodents, which catabolizes progesterone into biologically inactive $20{\alpha}$-hydroxypregn-4-en-3-one($20{\alpha}$-OHP). In this study was carried out the influence of $20{\alpha}$-HSD activity of ovarian function, we investigated changes in ovarian cytosol $20{\alpha}$-HSD activity and serume progesterone concentration during the estrous cycles and pregnancy in rat. During the estrous cycles, the $20{\alpha}$-HSD activities were highest on the progestrous, but serum progesterone concentration was lowest on this phase. During the pregnancy, the $20{\alpha}$-HSD activities were relatively higher early pregnancy(day-1-3 gestation) and late pregnancy(day 21 to parturition), serum progesterone concentration was maintained significantly high to day 19 of gestation. The $20{\alpha}$-HSD activities were lower during the middle pregnancy. From these results, ovarian $20{\alpha}$-HSD activities may possibly act as physiologically very important in the control and maintenance of estrous cycles in rat.

• 대한수의학회지
• /
• 제34권4호
• /
• pp.873-880
• /
• 1994

Progesterone catabolizing enzyme, the enzyme $20{\alpha}$-hydroxysteroid deltydrgenase($20{\alpha}$-HSD) is pivotal in the regulation of ovarian function in rodents, which catabolizes progesterone into biologically inactive $20{\alpha}$ hydroxypregn-4-en-3-one($20{\alpha}$-OHP). In this study was carried out the influence of $20{\alpha}$-HSD activity to ovarian function and regulation such as ovulation, formation of corpus luteum, maintenance of estrous cycles and pregnancy, we investigated changes in activities of the splenic macrophages and ovarian histological findings in rat. During the estrous cycles, the ratious of phagocytotic macrophage in splenic adherent cells were highest on the proestrous, but they were lowest on metestrous. During the pregnancy, the ratious of phagocytotic macrophages in splenic adhrent cells were lowest by 1 day and then significantly increased toward the pregnancy, which were highest pregnancy on day 12. On histological findings in rat ovary, the mean number of growing, antral and mature follicles were 15.9(72.9%), 3.4(15.9%), and 2.4(11.2%), respectively. Growing follicles reached to lowest number at diestrus and mature follicle reached to lowest number at metestrus. The numbers of corpus luteums per tissue section of the ovary were 14.4 and the number of normal and atretic follicles were 11.0(76.4%) and 3.4(23.6%), respectively. The number of corpus luteum with vacolated cell were 1.7(11.8%). In this study suggests splenic macrophages are as a source of the substance which maintainer progesterone secretion from luteal cells, and are recognized pass the vessels and reside in the fresh corpora lutea soon after ovulation via inflammatory reactions, and these macrophages are felt to have a stimulatory effect on the formation of cropora lutea. In view of the results include previous report, ovarian $20{\alpha}$-hydroxysteroid dehydrogenase enzyme and splenic macrophages consider play central role in the control and maintenance of estrous cycles and pregnancy, and also applicable to both clinical and research in a wide variety such as control of reproductive system.