Effect of nacl load administered to the fetus on the bidirectional
movement of 51cr-edta across the rat placenta.
J., Tulc, and Tulcov[acute]a B.
Department of Pharmacology, 2nd Faculty of Medicine and Department
of Physiology, 1st Faculty of Medicine, Charles University, Prague,
Czech Republic
APStracts 2:0304R, 1995.
A hypothesis that in the rat fluid circulates across the placenta, the
circulation being maintained by active transport of Na+ from mother
to fetus, has been tested. The hypothesis predicts that increasing
Na+ supply to the fetus would increase the circulation of fluid which
would increase convective flow of extracellular probes in the fetal
-maternal direction. Clearance of 51Cr-EDTA from mother to fetus, Kmf,
and from fetus to mother, Kfm, has been measured in anesthetized
rats. Immediately before the transfer measurement the fetuses were
injected intravenously with 10 [mu]l of isotonic glucose (controls)
or with 30 [mu]l or 300 [mu]l of isotonic saline, or with 10 [mu]l,
30 [mu]l or 60 [mu]l of 9% solution of NaCl. In controls Kmf of 51Cr
-EDTA was 2.0 +/- 0.7 [mu]l min-1, and Kfm was 4.3 +/- 1.0 [mu]l min
-1. Injecting the fetus with NaCl had no effect on Kmf while it
increased Kfm significantly in a dose dependent way. These
observations support the hypothesis tested.
Received 10 March 1995; accepted in final form 1 November 1995.
APS Manuscript Number R196-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 30 November 95