The corticosteroid hormone synthetic pathway The corticosteroid hormone synthetic pathway. The pathways illustrated are present in differing amounts in the steroid-producing tissues: adrenal glands, ovaries, and testes. In the adrenal glands, mineralocorticoids from the zona glomerulosa, glucocorticoids from the zona fasciculata, and androgens (and estrogens) from the zona reticularis are produced. The major adrenal androgen is androstenedione, because the activity of 17-ketoreductase is relatively low. The adrenal gland does secrete some testosterone and estrogen, however. The pathways leading to the synthesis of mineralocorticoids and glucocorticoids are not present to any significant degree in the gonads; however, the testes and ovaries each produce both androgens and estrogens. Further metabolism of testosterone to dihydrotestosterone occurs in target tissues of the action of the enzyme 5α-reductase. DHEA, dehydroepiandrosterone. Source: Endocrine Disorders, CURRENT Diagnosis & Treatment Pediatrics, 23e Citation: Hay WW, Jr., Levin MJ, Deterding RR, Abzug MJ. CURRENT Diagnosis & Treatment Pediatrics, 23e; 2016 Available at: https://accessmedicine.mhmedical.com/DownloadImage.aspx?image=/data/books/1795/ped23_ch34_f008.png&sec=125747253&BookID=1795&ChapterSecID=125747021&imagename= Accessed: October 23, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved