Document Detail

Relationships of circulating pregnanolone isomers and their polar conjugates to the status of sex, menstrual cycle, and pregnancy.
MedLine Citation:
PMID:  17911398     Owner:  NLM     Status:  MEDLINE    
Pregnanolone isomers (PIs) and their polar conjugates (PICs) modulate ionotropic receptors such as gamma-aminobutyric acid or pregnane X receptors. Besides, brain synthesis, PI penetrates the blood-brain barrier. We evaluated the physiological importance of PI respecting the status of sex, menstrual cycle, and pregnancy. Accordingly, circulating levels of allopregnanolone (P3alpha 5alpha ), isopregnanolone (P3beta 5alpha ), pregnanolone (P3alpha 5beta ), epipregnanolone (P3beta 5beta ), their polar conjugates, and related steroids were measured in 15 men (M), 15 women in the follicular phase (F), 16 women in the luteal phase (L), and 30 women in the 36th week of gestation (P) using GC-MS. The steroid levels were similar in M and F, increased about thrice in L and escalated in P (38-410 times compared with F). The PICs were prevalent over the PIs (16-150 times). Higher ratios of 5alpha-PIC to 5alpha-PI found in P indicate the more intensive conjugation of 5alpha-PI during pregnancy. This mechanism probably provides for the elimination of neuroinhibitory P3alpha 5alpha in the maternal compartment. Additionally, our result points to a limited sulfation capacity for neuroinhibitory P3alpha 5beta in P. In contrast to the situation in M, F, and L where the P3alpha 5beta C is the most abundant PIC, and P3alpha 5beta is present in minor quantities compared with the P3alpha 5alpha, P3alpha 5beta may acquire physiological importance during pregnancy, contributing to the sustaining thereof. On the other hand, the declining formation of P3alpha 5beta may participate in the initiation of parturition, given the relative abundance of the steroid, its potency to suppress the activity of oxytocin-producing cells and its effectiveness in uterine relaxation.
Radmila Kancheva; Martin Hill; David Cibula; Helena Vceláková; Lyudmila Kancheva; Jana Vrbíková; Tomás Fait; Antonín Parízek; Luboslav Stárka
Related Documents :
10739848 - Pregnancy and sex steroid hormones enhance circulating calcitonin gene-related peptide ...
21367098 - 112 expression of dna methyltransferases (dnmt) in placental tissues during early pregn...
21210448 - Prediction of spontaneous preterm delivery from maternal factors, obstetric history and...
21250908 - Maternal and fetal angiotensin-converting enzyme gene insertion/deletion polymorphism n...
20547518 - Safety of triptans for migraine headaches during pregnancy and breastfeeding.
1125148 - Neonatal hyperbilirubinaemia following the use of oxytocin in labour.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The Journal of endocrinology     Volume:  195     ISSN:  0022-0795     ISO Abbreviation:  J. Endocrinol.     Publication Date:  2007 Oct 
Date Detail:
Created Date:  2007-10-03     Completed Date:  2008-06-11     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0375363     Medline TA:  J Endocrinol     Country:  England    
Other Details:
Languages:  eng     Pagination:  67-78     Citation Subset:  IM    
Institute of Endocrinology, Národnítrída 8, CZ 116 94 Prague 1, Czech Republic.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Analysis of Variance
Follicular Phase / blood
Luteal Phase / blood
Menstrual Cycle / blood*
Middle Aged
Pregnancy / blood*
Pregnancy Trimester, Third / blood
Pregnanolone / blood*
Reg. No./Substance:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Ontogenic and nutritional regulation of steroid receptor and IGF-I transcript abundance in the prepu...
Next Document:  Fetal programming of colon cancer in adult rats: correlations with altered neonatal growth trajector...