Document Detail

Relationship of fetal alanine uptake and placental alanine metabolism to maternal plasma alanine concentration.
MedLine Citation:
PMID:  9843735     Owner:  NLM     Status:  MEDLINE    
Uterine and umbilical uptakes of alanine (Ala) were measured in 10 ewes before (control) and during intravenous infusion of Ala, which increased maternal arterial Ala concentration from 115 +/- 14 to 629 +/- 78 microM (P < 0.001). In 8 of these ewes, placental Ala fluxes were traced by constant intravenous infusion of L-[3,3,3-2H3]Ala in the mother and L-[1-13C]Ala in the fetus. Rates are reported as micromoles per minute per kilogram fetus. Ala infusion increased uterine uptake (2.5 +/- 0.6 to 15.6 +/- 3.1, P < 0.001), umbilical uptake (3.1 +/- 0.5 to 6.9 +/- 0.8, P < 0.001), and net uteroplacental utilization (-0.7 +/- 0.8 to 8.6 +/- 2.7, P < 0.01) of Ala. Control Ala flux to fetus from mother (Rf,m) was much less than the Ala flux to fetus from placenta (Rf,p) (0.17 +/- 0.04 vs. 5. 0 +/- 0.6). Two additional studies utilizing L-[U-13C]Ala as the maternal tracer confirmed the small relative contribution of Rf,m to Rf,p. During maternal Ala infusion, Rf,m increased significantly (P < 0.02) but remained a small fraction of Rf,p (0.71 +/- 0.2 vs. 7.3 +/- 1.3). We conclude that maternal Ala entering the placenta is metabolized and exchanged for placental Ala, so that most of the Ala delivered to the fetus is produced within the placenta. An increase in maternal Ala concentration increases placental Ala utilization and the fetal uptake of both maternal and placental Ala.
M Timmerman; M Chung; R B Wilkening; P V Fennessey; F C Battaglia; G Meschia
Related Documents :
24176505 - Steroid and steroid glucuronide profiles in urine during pregnancy determined by liquid...
15774525 - Circulating levels of nitric oxide and vascular endothelial growth factor throughout ov...
23845775 - Evaluation of the impact of maternal smoking on ultrasound and endocrinological markers...
10739535 - Nitric oxide modulates angiotensin ii-induced drinking behavior in the near-term ovine ...
24797575 - Global, regional, and national levels and causes of maternal mortality during 1990-2013...
8229945 - Effect of addition of autologous prostatic fluid on the fertility of frozen-thawed dog ...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The American journal of physiology     Volume:  275     ISSN:  0002-9513     ISO Abbreviation:  Am. J. Physiol.     Publication Date:  1998 Dec 
Date Detail:
Created Date:  1999-02-03     Completed Date:  1999-02-03     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:  E942-50     Citation Subset:  IM    
Department of Obstetrics and Gynecology, Erasmus University, Rotterdam, The Netherlands 3000 DR.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Alanine / blood*,  pharmacokinetics*
Amino Acids / blood,  metabolism
Fetal Blood / metabolism
Fetus / metabolism*
Osmolar Concentration
Placenta / metabolism*
Pregnancy, Animal / blood*
Sheep / embryology
Umbilical Cord / metabolism
Grant Support
Reg. No./Substance:
0/Amino Acids; 56-41-7/Alanine

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

Previous Document:  Pinealectomy causes glucose intolerance and decreases adipose cell responsiveness to insulin in rats...
Next Document:  Endurance training changes in lipolytic responsiveness of obese adipose tissue.