Document Detail


Placental transport of threonine and its utilization in the normal and growth-restricted fetus.
MedLine Citation:
PMID:  9176191     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Placental transport and fetoplacental utilization of threonine (Thr) were compared at 130 +/- 1 days gestational age between seven control ewes (C) and six ewes in which intrauterine growth restriction (IUGR) had been induced by exposure to high ambient temperature from 33 +/- 1 to 112 +/- 2 days of gestation. The fluxes were measured using simultaneous intravenous infusions of L-[1-13C]Thr into the mother and L-[U-14C]Thr into the fetus. The IUGR group had less fetal weight (1.27 +/- 0.14 vs. 3.10 +/- 0.10 kg, P < 0.01) and placental weight (120 +/- 17 vs. 295 +/- 14 g, P < 0.01) than the C group. The direct flux of maternal Thr into the fetal systemic circulation was less in the IUGR fetuses, both relative to fetal weight (1.40 +/- 0.19 vs. 2.19 +/- 0.18 mumol.min-1.kg fetus-1, P = 0.0107) and placental weight (1.5 +/- 0.2 vs. 2.3 +/- 0.2 mumol.min-1.100 g placenta-1, P = 0.0187). In both groups, there was excretion of CO2 produced from fetal Thr. The rate of CO2 production from fetal plasma Thr carbon by fetus plus placenta was reduced in the IUGR group (1.50 +/- 0.23 vs. 2.86 +/- 0.32 mumol.min-1.kg fetus-1, P = 0.0065). We conclude that the flux of maternal Thr into the IUGR fetus is markedly reduced because of a reduction in placental mass and because of a weight-specific reduction in Thr placental transport. The reduced flux is routed into fetal Thr accretion via a decrease in fetal Thr oxidation.
Authors:
A H Anderson; P V Fennessey; G Meschia; R B Wilkening; F C Battaglia
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The American journal of physiology     Volume:  272     ISSN:  0002-9513     ISO Abbreviation:  Am. J. Physiol.     Publication Date:  1997 May 
Date Detail:
Created Date:  1997-07-08     Completed Date:  1997-07-08     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0370511     Medline TA:  Am J Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  E892-900     Citation Subset:  IM    
Affiliation:
Department of Pediatrics, University of Colorado School of Medicine, Denver 80262, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Biological Transport
Body Weight
Carbon Dioxide / blood
Female
Fetal Growth Retardation / metabolism*
Fetus / anatomy & histology,  metabolism
Maternal-Fetal Exchange
Organ Size
Placenta / anatomy & histology,  metabolism*
Pregnancy
Reference Values
Sheep
Threonine / blood,  metabolism*
Grant Support
ID/Acronym/Agency:
DK-34914/DK/NIDDK NIH HHS; DK-48520/DK/NIDDK NIH HHS; HD-20761/HD/NICHD NIH HHS
Chemical
Reg. No./Substance:
124-38-9/Carbon Dioxide; 72-19-5/Threonine

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


Previous Document:  Progesterone-induced changes in sleep in male subjects.
Next Document:  Energy expenditure of adult male rhesus monkeys during the first 30 mo of dietary restriction.