Inhibitory effect of glucocorticoid and stimulatory effect of human chorionic gonadotropin on ovarian carbonyl reductase in rats.

Effects of three glucocorticoids on ovulation, and on content and activity of ovarian carbonyl reductase in rats were investigated. Glucocorticoid treatment caused both significant decrease in ovarian and uterine weights, blockade of ovulation and marked decrease in content and activity of ovarian carbonyl reductase. Furthermore, the weak immunoreactivity to antibody against ovarian carbonyl reductase was shown in the theca cells and the interstitial gland cells in the glucocorticoid-treated ovary. The treatment with hCG (LH activity specific) restored the ovarian weight, and both the content and activity of ovarian carbonyl reductase, which were inhibited by glucocorticoids, to control level as well as ovulation. These results indicate that the ovarian carbonyl reductase may be closely involved in ovarian function, especially ovulation, and may be an LH-dependent enzyme, because it is well known that glucocorticoids inhibit both LH surge and ovulation in rats.