alexa Developmental and functional biology of the primate fetal adrenal cortex.


Journal of Pulmonary & Respiratory Medicine

Author(s): Mesiano S, Jaffe RB

Abstract Share this page

Abstract The unique characteristics of the primate (particularly human) fetal adrenal were first realized in the early 1900s when its morphology was examined in detail and compared with that of other species. The unusual architecture of the human fetal adrenal cortex, with its unique and disproportionately enlarged fetal zone, its compact definitive zone, and its dramatic remodeling soon after birth captured the interest of developmental anatomists. Many detailed anatomical studies describing the morphology of the developing human fetal adrenal were reported between 1920 and 1960, and these morphological descriptions have not changed significantly. More recently, it has become clear that fetal adrenal cortical growth involves cellular hypertrophy, hyperplasia, apoptosis, and migration and is best described by the migration theory, i.e. cells proliferate in the periphery, migrate centripetally, differentiate during their migration to form the functional cortical zones, and then likely undergo apoptosis in the center of the cortex. Consistent with this model, cells of intermediate phenotype, arranged in columnar cords typical of migration, have been identified between the definitive and fetal zones. This cortical area has been referred to as the transitional zone and, based on the expression of steroidogenic enzymes, we consider it to be a functionally distinct cortical zone. Elegant experiments during the 1950s and 1960s demonstrated the central role of the primate fetal adrenal cortex in establishing the estrogenic milieu of pregnancy. Those findings were among the first indications of the function and physiological role of the human fetal adrenal cortex and led Diczfalusy and co-workers to propose the concept of the feto-placental unit, in which DHEA-S produced by the fetal adrenal cortex is used by the placenta for estrogen synthesis. Tissue and cell culture techniques, together with improved steroid assays, revealed that the fetal zone is the primary source of DHEA-S, and that its steroidogenic activity is regulated by ACTH. In recent years, function of the human and rhesus monkey fetal adrenal cortical zones has been reexamined by assessing the localization and ontogeny of steroidogenic enzyme expression. The primate fetal adrenal cortex is composed of three functionally distinct zones: 1) the fetal zone, which throughout gestation does not express 3 beta HSD but does express P450scc and P450c17 required for DHEA-S synthesis; 2) the transitional zone, which early in gestation is functionally identical to the fetal zone but late in gestation (after 25-30 weeks) expresses 3 beta HSD, P450scc, and P450c17, and therefore is the likely site of glucocorticoid synthesis, and 3) the definitive zone, which lacks P450c17 throughout gestation but late in gestation (after 22-24 weeks) expresses 3 beta HSD and P450scc, and therefore is the likely site of mineralocorticoid synthesis. Indirect evidence, based on effects of P450c21 deficiency and maternal estriol concentrations, indicate that the fetal adrenal cortex produces cortisol and DHEA-S early in gestation (6-12 weeks). However, controversy exists as to whether cortisol is produced de novo or derived from the metabolism of progesterone, as data regarding the expression of 3 beta HSD in the fetal adrenal cortex early in gestation are conflicting. During the 1960s, Liggins and colleagues demonstrated that in the sheep, cortisol secreted by the fetal adrenal cortex late in gestation regulates maturation of the fetus and initiates the cascade of events leading to parturition. Those pioneering discoveries provided insight into the mechanism underlying the timing of parturition and therefore were of particular interest to obstetricians and perinatologists confronted with the problems of preterm labor. However, although cortisol emanating from the fetal adrenal cortex promotes fetal maturation in primates as it does in sheep, its role in the regulation of primate parturition, unlike that in sheep This article was published in Endocr Rev and referenced in Journal of Pulmonary & Respiratory Medicine

Relevant Expert PPTs

Relevant Speaker PPTs

  • Shoude Jin
    Mechanisms of Chronic obstructive pulmonary disease and airway smooth muscle remodeling: the potential roles of Abhd2
    PDF Version
  • Alsayed Alnahal
    Urinary netrin-1 predict early ischemic acute kidney injury after cardiopulmonary bypass
    PPT Version | PDF Version
  • Ping Yang
    Chronic obstructive pulmonary disease (COPD) complicating early-stage lung cancer (LC)
    PDF Version
  • Gunilla Lindqvist
    Chronic obstructive pulmonary disease: A study of the relationship between patients’ feeling of guilt due to their belief of the disease being self inflicted
    PDF Version
  • Roger Mark Engel
    The effect of including manual therapy in the management of mild chronic obstructive pulmonary disease – a randomized controlled trial
    PDF Version
  • Rupal Patel Mansukhani
    Correlation of Medication Therapy in Chronic Obstructive Pulmonary Disease(COPD) Patients with 30-day Readmission Rates
    PPT Version | PDF Version
  • Mohamed Hamdy Ibrahim
    Prevalence of venous sinus stenosis in Pseudo Tumor Cerebri (PTC) using Digital Subtraction Angiography (DSA)
    PPT Version | PDF Version
  • Hadeel Faisal Gad
    In-vitro analysis of cytokines responses of visceral leishmaniasis and pulmonary tuberculosis patients to homologous and heterologous antigen stimulation
    PPT Version | PDF Version
  • Biplab Mishra
    Compression of hepatoduodenal ligament by sponges during perihepatic packing for liver trauma leading to difficult maneuvering of angiography catheter through common hepatic artery: ‘Mishra Phenomenon’
    PPT Version | PDF Version
  • Xin Wang
    IL17 Pathway Involves Moderating Pulmonary Hypertension, a common complication of COPD, in Statins Therapy in Smoking Rats
    PPT Version | PDF Version

Recommended Conferences

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version