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Updated: Oct 20, 2026

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model
08:08

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

Published on: June 18, 2013

Sulfate transport in human placenta: further evidence for a sodium-independent mechanism

D E Cole1, N Rastogi

  • 1Department of Pediatrics, Dalhousie University, Halifax, NS, Canada.

Biochimica Et Biophysica Acta
|May 7, 1991
PubMed

Sulfate transport in isolated placental brush-border membrane vesicles has properties consistent with an anion exchange process. To ascertain the relevance of this finding to sulfate accumulation by the fetus and placenta in vivo, we examined sulfate transport in human placental tissue slices, comparing sulfate uptake with that of a non-metabolizable amino acid marker, alpha-aminoisobutyrate (AIB). In contrast to AIB, which was actively concentrated from physiological media, sulfate uptake by the placenta slice was concentrative only in the absence of sodium and at low pH. Uptake of sulfate reached a steady state after 60 min. It was blocked by DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonate), a specific inhibitor of anion transport, but not by ouabain. We found no evidence for Na(+)-dependent uptake of sulfate in incubated placental tissue. It seems unlikely that Na(+)-dependent sulfate transport by the placenta can be responsible for net sulfate accumulation by the human fetus.

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