Fetal adrenals release which hormone predominantly:March 2009, September 2010

Ans. D: CoisoneFetal adrenals shows hyperophy of the reticular zone (fetal zone), which is the site of synthesis of oestriol precursor, coisol and dehydroepiandrosterone.After 12 weeks of gestation, the activity of 3 p-hydroxysteroid dehydrogenase (HSD3B) decreases in fetal adrenal and sulfokinase activity increases.At that time (during the mid-gestation, 12 to 22 weeks) the major steroid products are DHEA and DHEA Sulfate (DHEA-S).During the mid-gestation (12 to 22 weeks), the aromatase activity and sulfokinase activity increases. So Placenta itself utilizes fetal DHEA and DHEA-S as substrate for estrone and estradiol as precursors.