Linked Life Data

17959886

Source:http://linkedlifedata.com/resource/pubmed/id/17959886

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2007-10-25
pubmed:abstractText
As gestation progresses, human fetal adrenals (HFA) initiate the production of cortisol, which increases placental corticotropin-releasing hormone (CRH) biosynthesis. While adrenocorticotrophic hormone (ACTH) is important for the onset of cortisol production, the late gestational surge in cortisol production occurs despite falling ACTH levels in the fetal circulation. The authors determine if CRH directly regulates the expression of the ACTH receptor (ACTHR) in HFA definitive/transitional zone (DZ/TZ) cells. DZ/TZ cells isolated from midgestation HFA were cultured before treatment with 0.01 nM to 100 nM CRH or ACTH. Cortisol was measured by radioimmunoassay. Real-time reverse-transcriptase polymerase chain reaction was used to measure ACTHR mRNA. Whole-cell ACTH binding studies were performed using I(125) (Tyr-23) ACTH. CRH produced a dose-dependent rise in cortisol production and caused a time-dependent increase in ACTHR mRNA levels between 12 and 24 hours. As little as 0.1 nM CRH induced ACTHR transcript by 12-fold at 24 hours. Together with ACTH 0.01 nM, 0.03 or 0.1 nM CRH increased ACTHR expression more than ACTH alone. Binding assays demonstrated a 3.5-fold increase in ACTHR protein at 48 hours with combined CRH and ACTH treatment. Physiologic levels of CRH seen in the late-gestation fetus stimulate DZ/TZ ACTHR expression. Since placental CRH production increases strikingly near the end of gestation, the authors suggest that CRH-induced ACTH receptor expression may increase TZ responsiveness to circulating ACTH and contribute to the late gestational rise in cortisol secretion by the HFA, participating in an endocrine cascade that is involved in fetal organ maturation and potentially in the timing of human parturition.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1933-7205
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
578-87
pubmed:dateRevised
2008-1-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The regulation of adrenocorticotrophic hormone receptor by corticotropin-releasing hormone in human fetal adrenal definitive/transitional zone cells.
pubmed:affiliation
Department of Obstetrics & Gynecology, Division of Reproductive Endocrinology and Infertility, University of Texas Southwestern Medical Center, Dallas, TX 75390-9032, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural