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. 1995 Aug 15;487(Pt 1):159–167. doi: 10.1113/jphysiol.1995.sp020868

Concentrations of Na+ and Cl- in transplacental ultrafiltrate in sheep.

J J Faber 1, D F Anderson 1
PMCID: PMC1156606  PMID: 7473245

Abstract

1. Maternal blood was made transiently hypertonic by rapid I.V. infusion of a concentrated mannitol solution into pregnant ewes bearing lambs with an indwelling flow sensor and vascular catheters. 2. The transplacental flows of water and of Na+ and Cl- were calculated from the umbilical arteriovenous differences in the concentrations of 125I-labelled albumin and electrolytes, and the fetal placental blood flow. 3. The reflection coefficients of Na+ and Cl- were calculated by means of the Patlak equation and found to be 0.85 +/- 0.04 and 0.68 +/- 0.04 (means +/- S.E.M.). The filtration coefficient was 1.02 x 10(-7) +/- 0.12 x 10(-7) cm5 dyne-1 s-1. 4. The results fitted best to an equivalent pore radius in the placental barrier smaller than the currently accepted 0.44 nm but not less than 0.35 nm.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Anderson D. F., Faber J. J. Regulation of fetal placental blood flow in the lamb. Am J Physiol. 1984 Sep;247(3 Pt 2):R567–R574. doi: 10.1152/ajpregu.1984.247.3.R567. [DOI] [PubMed] [Google Scholar]
  2. Anderson D. F., Parks C. M., Faber J. J. Fetal O2 consumption in sheep during controlled long-term reductions in umbilical blood flow. Am J Physiol. 1986 Jun;250(6 Pt 2):H1037–H1042. doi: 10.1152/ajpheart.1986.250.6.H1037. [DOI] [PubMed] [Google Scholar]
  3. Armentrout T., Katz S., Thornburg K. L., Faber J. J. Osmotic flow through the placental barrier of chronically prepared sheep. Am J Physiol. 1977 Oct;233(4):H466–H474. doi: 10.1152/ajpheart.1977.233.4.H466. [DOI] [PubMed] [Google Scholar]
  4. Boyd R. D., Haworth C., Stacey T. E., Ward H. T. Permeability of the sheep placenta to unmetabolized polar non-electrolytes. J Physiol. 1976 Apr;256(3):617–634. doi: 10.1113/jphysiol.1976.sp011342. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bresler E. H., Groome L. J. On equations for combined convective and diffusive transport of neutral solute across porous membranes. Am J Physiol. 1981 Nov;241(5):F469–F476. doi: 10.1152/ajprenal.1981.241.5.F469. [DOI] [PubMed] [Google Scholar]
  6. CZACZKES J. W., ULLMANN T. D., ULLMANNL, BAR-KOCHBA Z. Determination of the red blood cell content of water, sodium, and potassium in normal subjects. J Lab Clin Med. 1963 May;61:873–878. [PubMed] [Google Scholar]
  7. Conrad E. E., Jr, Faber J. J. Water and electrolyte acquisition across the placenta of the sheep. Am J Physiol. 1977 Oct;233(4):H475–H487. doi: 10.1152/ajpheart.1977.233.4.H475. [DOI] [PubMed] [Google Scholar]
  8. Curry F. E., Michel C. C., Mason J. C. Osmotic reflextion coefficients of capillary walls to low molecular weight hydrophilic solutes measured in single perfused capillaries of the frog mesentery. J Physiol. 1976 Oct;261(2):319–336. doi: 10.1113/jphysiol.1976.sp011561. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. DURBIN R. P. Osmotic flow of water across permeable cellulose membranes. J Gen Physiol. 1960 Nov;44:315–326. doi: 10.1085/jgp.44.2.315. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Faber J. J., Anderson D. F. Model study of placental water transfer and causes of fetal water disease in sheep. Am J Physiol. 1990 May;258(5 Pt 2):R1257–R1270. doi: 10.1152/ajpregu.1990.258.5.R1257. [DOI] [PubMed] [Google Scholar]
  11. MESCHIA G., BATTAGLIA F. C., BARRON D. H. A comparison of the freezing points of fetal and maternal plasmas of sheep and goat. Q J Exp Physiol Cogn Med Sci. 1957 Apr;42(2):163–170. doi: 10.1113/expphysiol.1957.sp001247. [DOI] [PubMed] [Google Scholar]
  12. Patlak C. S., Goldstein D. A., Hoffman J. F. The flow of solute and solvent across a two-membrane system. J Theor Biol. 1963 Nov;5(3):426–442. doi: 10.1016/0022-5193(63)90088-2. [DOI] [PubMed] [Google Scholar]
  13. Thornburg K. L., Binder N. D., Faber J. J. Diffusion permeability and ultrafiltration-reflection-coefficients of Narand Cl- in the near-term placenta of the sheep. J Dev Physiol. 1979 Feb;1(1):47–60. [PubMed] [Google Scholar]
  14. Thornburg K. L., Binder N. D., Faber J. J. Distribution of ionic sulfate, lithium, and bromide across the sheep placenta. Am J Physiol. 1979 Jan;236(1):C58–C65. doi: 10.1152/ajpcell.1979.236.1.C58. [DOI] [PubMed] [Google Scholar]
  15. Wolf M. B., Watson P. D. Measurement of osmotic reflection coefficient for small molecules in cat hindlimbs. Am J Physiol. 1989 Jan;256(1 Pt 2):H282–H290. doi: 10.1152/ajpheart.1989.256.1.H282. [DOI] [PubMed] [Google Scholar]

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