Dehydrogenase and Oxoreductase Activities of Porcine Placental 11Beta-Hydroxysteroid Dehydrogenase.

摘要

Dehydrogenase (cortisol to cortisone) and oxoreductase (cortisone to cortisol) activities of porcine placental 11Beta-hydroxysteroid dehydrogenase (11beta-HSD) were measured in tissue fragment cultures on day 75 of gestation. Dehydrogenase activity was over fivefold greater than oxoreductase activity (p less than .001). There were positive linear associations (p less than . 01) between net dehydrogenase activity (dehydrogenase minus oxoreductase) and fetal weight, fetal length, and placental weight. These data indicate a predominance of placental 11Beta-HSD dehydrogenase activity at this gestational stage that would insure a net conversion of cortisol to cortisone as it traverses the placenta. The data further suggest that 11Beta-HSD activities may provide an optimal glucocorticoid environment that is supportive of enhanced fetal and placental growth.