MEDLINE Journals

    Placental uptake and transport of ACP, a neutral nonmetabolizable amino acid, in an ovine model of fetal growth restriction.

    Authors
    de Vrijer B, Regnault TR, Wilkening RB, et al. 
    Source
    Am J Physiol Endocrinol Metab 2004 Dec; 287(6) :E1114-24.
    Abstract

    Reductions in fetal plasma concentrations of certain amino acids and reduced amino acid transport in vesicle studies suggest impaired placental amino acid transport in human fetal growth restriction (FGR). In the present study, we tested the hypothesis of an impairment in amino acid transport in the ovine model of hyperthermia-induced FGR by determining transplacental and placental retention and total placental clearance of a branched-chain amino acid (BCAA) analog, the nonmetabolizable neutral amino acid aminocyclopentane-1-carboxylic acid (ACP), in singleton control (C) and FGR pregnancies at 135 days gestation age (dGA; term 147 dGA). At study, based on the severity of the placental dysfunction, FGR fetuses were allocated to severe (sFGR, n = 6) and moderate FGR (mFGR, n = 4) groups. Fetal (C, 3,801.91 +/- 156.83; mFGR, 2,911.33 +/- 181.35; sFGR, 1,795.99 +/- 238.85 g; P < 0.05) and placental weights (C, 414.38 +/- 38.35; mFGR, 306.23 +/- 32.41; sFGR, 165.64 +/- 28.25 g; P < 0.05) were reduced. Transplacental and total placental clearances of ACP per 100 g placenta were significantly reduced in the sFGR but not in the mFGR group, whereas placental retention clearances were unaltered. These data indicate that both entry of ACP into the placenta and movement from the placenta into fetal circulation are impaired in severe ovine FGR and support the hypothesis of impaired placental BCAA transport in severe human FGR.

    Mesh
    Animals
    Biological Transport
    Blood Glucose
    Body Temperature
    Cycloleucine
    Ethanol
    Female
    Fetal Growth Retardation
    Gestational Age
    Lactic Acid
    Osmolar Concentration
    Oxygen Consumption
    Placenta
    Pregnancy
    Regional Blood Flow
    Sheep
    Umbilicus
    Uterus
    Language

    eng

    Pub Type(s)
    Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.
    PubMed ID

    15315907

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