Are There Membrane-Lined Channels through the Trophoblast? A Study with Lanthanum Hydroxide

  • Peter Kaufmann
  • Hobe Schroeder
  • Heinz-Peter Leichtweiss
  • Elke Winterhager
Part of the Trophoblast Research book series (TR)


Transfer experiments by Stulc et al. (1969) gave evidence for the existence of water-filled routes, so-called pores or channels, across the rabbit placenta. Their radius was calculated to be approximately 10 nm. These findings have been confirmed for the guinea pig placenta by Thornburg and Faber (1977) as well as by Hedley and Bradbury (1980). Morphological studies of both placentae, however, failed to demonstrate structural correlates, i.e., membrane-lined pathways across the trophoblast from the maternal lacunar surface to the basal trophoblastic surface that faces the fetal capillaries (Enders, 1965; Firth and Farr, 1977; Kaufmann and Davidoff, 1977). Among large numbers of syncytiotrophoblastic intracellular membrane systems like endoplasmic reticulum, Golgi cisternae, and absorptive tubules, structures with apparent luminal contacts to either surface are missing. In a recent publication, Gammal (1985) described so-called syncytial channels in the rhesus monkey placenta. These structures reported by Gammal are not comparable with those discussed in the present publication for several reasons: the “channels” described by Gammal are lamellar spaces rather than tubular channels, their luminal diameters range from 50 to 100 nm, and these “channels” are restricted to the superficial zone of the syncytiotrophoblast and never reach the basal trophoblastic surface.


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  1. Dragsten, P.R., Blumenthal, R., and Handler, J.S. (1981) Membrane asymmetry in epithelia: is the tight junction a barrier to diffusion in the plasma membrane? Nature 294, 718–722.PubMedCrossRefGoogle Scholar
  2. Enders, A.C. (1965) A comparative study of the fine structure of the trophoblast in several hemochorial placentas. Am. J. Anat. 116, 29–68.PubMedCrossRefGoogle Scholar
  3. Firth, J.A. and Farr, A. (1977) Structural features and quantitative age-dependent changes in the intervascular barrier of the guinea-pig haemochorial placenta. Cell Tissue Res. 184, 507–516.PubMedGoogle Scholar
  4. Gammal, E.B. (1985) Syncytial channels in the villous trophoblast of the macaque. J. Anat. 141, 181–191.PubMedGoogle Scholar
  5. Hedly, R., Bradbury, M.B.W., (1980) Transport of palar non-electrolytes across the intact and perfused guinea-pig palcenta. Placenta1, 277 - 285.CrossRefGoogle Scholar
  6. Kaufmann, P. (1985) Influence of ischemia and artificial perfusion on placental ultra-structure and morphometry. Contr. Gynecol. Obstet. 13, 18–26.Google Scholar
  7. Kaufmann, P. and Davidoff, M. (1977) The guinea-pig placenta. Adv. Anat. Embryol. Cell Biol. 53 (2), 1–92.Google Scholar
  8. Kaufmann, P. and Schroeder, H. (1980) Protein transport across the guinea pig chorioallantoic placenta. XIth Int. Cong. Anat., Mexico City.Google Scholar
  9. Kaufmann, P., Schroeder, H., and Leichtweiss, H.-P. (1982) Fluid shift across the placenta: II. Fetomaternal transfer of horseradish peroxidase in the guinea pig. Placenta 3, 339–348.PubMedCrossRefGoogle Scholar
  10. King, B.F. and Enders, A.C. (1971) Protein absorption by the guinea pig chorioallantoic placenta. Am. J. Anat. 130, 409–430.PubMedCrossRefGoogle Scholar
  11. Leichtweiss, H.-P. and Schroeder, H. (1971) Untersuchungen ueber den Glucosetransport durch die isolierte, beiderseits kuenstlich perfundierte meerschweinchenplacenta. Pflüegers Arch. 325, 139–148.CrossRefGoogle Scholar
  12. Revel, J.P. and Karnovsky, M.J. (1967) Hexagonal array of subunits in intercellular junctions of the mouse heart and liver. J. Cell Biol. 33, C7 - C12.PubMedCrossRefGoogle Scholar
  13. Schroeder, H. and Kaufmann, P. (1980) Do transtrophoblastic channels exist in the guinea-pig placenta. Int. Congr. Physiol. Sci., Szeged.Google Scholar
  14. Schroeder, H., Nelson, P., and Power, B. (1982) Fluid shift across the placenta. I. The effect of dextran T40 in the isolated guinea pig placenta. Placenta 3, 327–338.CrossRefGoogle Scholar
  15. Sibley, C.P., Bauman, K.F., and Firth, J. A. (1981) Ultrastructural study of the permeability of the guinea-pig placenta to horseradish peroxidase. Cell Tissue Res. 219, 637–647.PubMedGoogle Scholar
  16. Sideri, M., de Virgiliis, G., Rainoldi, R., and Remotti, G. (1983) The ultrastructural basis of the nutritional transfer: evidence of different patterns in the plasma membranes of the multilayered placental barrier. Trophoblast Res. 1, 15–26.Google Scholar
  17. Simionescu, N. (1981) Transcytosis and traffic of membranes in the endothelial cell. In: International Cell Biology, (ed.), G. Schweiger, Berlin, Springer Publishers.Google Scholar
  18. Stulc, J., Friederich, R., and Jiricka, Z. (1969) Estimation of the equivalent pore dimensions in the rabbit placenta. Life Sci. 8, 167–180.PubMedCrossRefGoogle Scholar
  19. Thornburg, K. and Faber, J.J. (1977) Transfer of hydrophilic molecules by placenta and yolk sac of the guinea pig. Am. J. Physiol. 233, C111 - C124.PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1987

Authors and Affiliations

  • Peter Kaufmann
    • 1
  • Hobe Schroeder
    • 2
  • Heinz-Peter Leichtweiss
    • 2
  • Elke Winterhager
    • 1
  1. 1.Abt. AnatomieRWTH AachenAachenWest Germany
  2. 2.Abt. experimentelle MedizinUniversitaets-FrauenklinikHamburg 20West Germany

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