Summary
The distribution of lanthanum chloride and horseradish peroxidase within the full-term chorioallantoic placenta of the rat was investigated 1 to 20 min after administration of these tracers into the maternal blood circulation.
Both tracers rapidly penetrate trophoblastic layer I and diffuse into the interspace between layers I and II. They are localized in extensive infoldings and caveolae of the outer surface of layer II. The syncytial character of layer II is confirmed at this developmental stage of the placenta. There is no vesicular uptake or penetration beyond layer II until 20 min after tracer administration. Our results indicate that trophoblastic layer II is the main barrier in the chorioallantoic rat placenta preventing the permeation of macromolecules from maternal to fetal compartments.
With freeze-fracturing, particulate structures of variable arrangement and size are found between adjacent cells of layer I. With goniometric analysis small gaps between the appositions of the membrane are observed. These structures are interpreted as tight and/or gap junctions during stages of assembly or disassembly.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Aoki, A., Metz, J., Forssmann, W.G.: Studies on the ultrastructure and permeability of the hemotrichorial placenta. II. Fetal capillaries and tracer administration into the fetal blood circulation. Cell Tiss. Res. 192, 409–422 (1978)
Anderson, J.W.: The placental barrier to gamma globulins in the rat. Amer. J. Anat. 104, 403–430 (1959)
Bennett, M.V.L.: Function of electrotonic junctions in embryonic and adult tissues. Fed. Proc. 32, 65–75 (1973)
Dancis, J.: The placenta in fetal nutrition and excretion. Amer. J. Obstet. Gynec. 84, 1749–1755 (1962)
Davies, J., Glaesser, S.R.: Histological and fine structural observations on the placenta of the rat. Acta anat. (Basel) 69, 542–608 (1968)
Elias, P.M., Friend, D.A.: Vitamin-A-induced mucous metaplasia. J. Cell Biol. 68, 173–188 (1976)
Enders, A.C.: A comparative study of the fine structure of the trophoblast in several hemochorial placentas. Amer. J. Anat. 116, 29–68 (1965)
Fels, R., Themann, H.: Die Permeabilität der Mäuseplacenta für Meerrettichperoxydase. Eine elektronenmikroskopische Untersuchung. Cytobiologie 3, 162–171 (1971)
Forssmann, W.G., Ito, S., Weihe, E., Aoki, A., Dym, M., Fawcett, D.W.: An improved perfusion fixation method for the male genital tract. Anat. Rec. 188, 307–314 (1977)
Forssmann, W.G., Metz, J., Heinrich, D.: Gap junctions in the hemotrichorial placenta of the rat. J. Ultrastruct. Res. 53, 374–381 (1975)
Franke, M.: Feinstruktur der Placenta. Elektronenoptische Untersuchungen über die reifende und reife Placenta der Ratte. Jena: VEB G. Fischer 1969
Friend, D.S., Gilula, N.B.: Variations in tight and gap junctions in mammalian tissues. J. Cell Biol. 53, 758–776 (1972)
Furshpan, E.J., Potter, D.D.: Low-resistance junctions between cells in embryos and tissue culture. Curr. Top. Dev. Biol. 3, 95–127 (1968)
Gilula, N.B.: Gap junctions and cell communication. In: International cell biology (eds. B.R. Brinkley and K.R. Porter), pp. 61–69. New York: Rockefeller Univers. Press 1977
Graham, R.C., Karnovsky, M.J.: The early stages of injected horseradish peroxidase in the proximal tubules of the mouse kidney: ultrastructural cytochemistry by a new technique. J. Histochem. Cytochem. 14, 291–302 (1966)
Herms, V., Heinrich, D., Kubli, F., Metz, J.: Über die Verteilung von Aminosäuren in der trächtigen Ratte: i.V., i.a. und i.f. Applikation von C14-L-Tyrosin. Z. Geburtsh. Perinat. 178, 337–341 (1974)
Herms, V., Heinrich, D., Metz, J., Kubli, F.: Konzentrationsunterschiede der freien Aminosäuren in fetalen und maternalen Kompartimenten am Ende der normalen und pathologischen Schwangerschaft. Z. Geburtsh. Perinat. 3, 188–199 (1975)
King, B.F.: The permeability of the guinea pig parietal yolk sac placenta to peroxidase and ferritin. Amer. J. Anat. 134, 365–376 (1972)
Loewenstein, W.R.: Permeability of membrane junctions. Ann. N.Y. Acad. Sci. 137, 441–472 (1966)
Luft, J.H.: Improvements in epoxy resin embedding methods. J. biophys. biochem. Cytol. 9, 409–414 (1961)
Mayersbach, H. von: Zur Frage des Proteinübergangs von der Mutter zum Foeten. I. Befunde an Ratten am Ende der Schwangerschaft. Z. Zellforsch. 48, 479–504 (1958)
Mazet, F., Cartaud, J.: Freeze-fracture studies of frog atrial fibres. J. Cell Sci. 22, 427–434 (1976)
Metz, J., Heinrich, D., Forssmann, W.G.: Ultrastructure of the labyrinth in the rat full term placenta. Anat. Embryol. 149, 123–148 (1976a)
Metz, J., Heinrich, D., Forssmann, W.G.: Gap junctions in hemodichorial and hemotrichorial placentae. Cell Tiss. Res. 171, 305–315 (1976b)
Millonig, G.: Advantages of a phosphate buffer for OsO4 solutions in fixation. J. appl. Physiol. 32, 1637–1645 (1961)
Montesano, R., Friend, D.S., Perrelet, A., Orci, L.: In vivo assembly of tight junctions in fetal rat liver. J. Cell Biol. 67, 310–319 (1975)
Padykula, H.A., Deren, I.J., Wilson, T.H.: Development of structure and function in the mammalian yolk sac. 1. Developmental morphology and vitamin B12 uptake of the rat yolk sac. Develop. Biol. 13, 311–318 (1966)
Quinlivan, L.G.: Fetomaternal transfer of I131 gamma globulin in the rat. Amer. J. Obstet. Gynec. 88, 415–420 (1964)
Reynolds, E.S.: The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J. Cell Biol. 17, 208–212 (1963)
Robertson, T.A., Archer, J.M., Papadimitriou, J.M., Walters, M.N.J.: Transport of horseradish peroxidase in the murine placenta. J. Path. 103, 141–147 (1971)
Schiebler, T.H., Knoop, A.: Histochemische und elektronenmikroskopische Untersuchungen an der Rattenplacenta. Z. Zellforsch. 50, 494–552 (1959)
Sonnhof, U., Richter, D.W., Taugner, R.: Electrotonic coupling between frog spinal motoneurons. An electrophysiological and morphological study. Brain Res. 138, 197–215 (1977)
Tillack, T.W.: The transport of ferritin across the placenta of the rat. Lab. Invest. 15, 896–909 (1966)
Author information
Authors and Affiliations
Additional information
Supported by the German Research Foundation
We are indebted to Mrs. Ch. Walenta and D. Labeille for technical assistance and stud. med. S. Meairs and Mrs. R. Botz for preparing the manuscript
Rights and permissions
About this article
Cite this article
Metz, J., Aoki, A. & Forssmann, W.G. Studies on the ultrastructure and permeability of the hemotrichorial placenta. Cell Tissue Res. 192, 391–407 (1978). https://doi.org/10.1007/BF00212321
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00212321