No abstract

No abstract

No abstract

Introduction. There are few descriptions of the placenta and associated tissues of the European hedgehog (Erinaceus europaeus) and here we present findings on a near-term pregnant specimen.Methods. Tissues were examined grossly and then formalin fixed and wax-embedded for histology and immunocytochemistry (cytokeratin) and resin embedded for lectin histochemistry.Results: Each of four well-developed and near term hoglets displayed a discoid, haemochorial placenta with typical labyrinth and spongy zones. In addition there was a paraplacenta i corporati g Reichert's e ra e a d a largely detached yolk sac. The trophoblast of the placenta contained diverse populations of granule which expressed most classes of glycan.Intercellular membranes were also glycosylated and this tended to be heavier in the labyrinth zone.Fetal capillary endothelium had glycosylated apical surfaces expressing sialic acid and various other glycans. Glycogen was present in large cells situated between the spongy zone and the endometrium. Tropho last cells i the place tal disc a d u der Reichert's e ra e, as well as yolk sac endoderm and mesothelium, were cytokeratin positive. Reichert's e ra e was heavily glycosylated. Yolk sac inner and outer endoderm expressed similar glycans except for Nacetylgalactosamine residues in endodermal acini.Discussion. New features of near-term hedgehog placenta and associated tissues are presented, including their glycosylation, and novel yolk sac acinar structures are described. The trophoblast of the place tal disc showed sig ifica t differe ces fro that u derlyi g Reichert's e ra e while the glycan composition of the membrane itself showed some similarity to that of rat thereby implying a degree of biochemical conservation of this structure.Key words: Place ta; Reichert's e ra e; yolk sac; histology; lecti s; cytokerati Highlights  The near-term placenta of Erinaceus europaeus was discoid and haemochorial  It was composed of labyrinth, spongy and junctional zones with a paraplacenta  Yolk sac haematopoiesis was still found to be present. The yolk sac contained endodermal acini with a specific surface glycan composition  Tropho last u der Reichert's e ra e was glycoge rich u like that found elsewhere *Highlights

No abstract