Permeability of the human placenta in vivo to four non-metabolized hydrophilic molecules

J Physiol. 1990 Dec:431:505-13. doi: 10.1113/jphysiol.1990.sp018343.

Abstract

1. Permeability of the human placenta to four permeants of different molecular size was measured at Caesarean section in seven normal full-term pregnancies. 2. Placental clearance for mannitol was 8.7 +/- 1.1 ml min-1 (mean +/- S.E.M.), lactulose 6.3 +/- 0.8, chromium ethylenediaminetetraacetic acid (CrEDTA) 3.7 +/- 0.5, and inulin 0.98 +/- 0.1. 3. The permeability data were analysed in terms of restricted diffusion through 'notional' water-filled pores and found to be incompatible with a single population of uniform pores.

MeSH terms

  • Adult
  • Birth Weight
  • Cell Membrane Permeability / physiology
  • Cesarean Section
  • Edetic Acid / pharmacokinetics
  • Female
  • Humans
  • Infant, Newborn
  • Inulin / pharmacokinetics
  • Lactulose / pharmacokinetics
  • Male
  • Mannitol / pharmacokinetics
  • Molecular Weight
  • Organ Size
  • Placenta / anatomy & histology
  • Placenta / metabolism*
  • Pregnancy

Substances

  • Mannitol
  • Lactulose
  • Inulin
  • Edetic Acid