The ultrastructural aspects of the appositional phase of interstitial blastocyst implantation in the guinea pig have been investigated using scanning and transmission electron microscopy. Blastocysts measured 28–34 µm in diameter and were encased in the zona pellucida. Trophoblast pseudopodia which penetrated the zona made contact with the underlying uterine epithelium and served, along with uterine epithelial contact with the zona, to hold the blastocyst over the subsequent site of implantation. Pseudopodia emanated from the embryonic pole of the blastocyst measured 2–4 µm in diameter and initiated uterine-blastocyst contact. Pseudopodia contained a cytoplasm rich in tubular mitochondria, rough endoplasmic reticulum, and Golgi apparatus and usually were found directed toward a sub-epithelial capillary plexus. These results suggest that the trophoblast pseudopodia are very active metabolically and may serve to align the blastocyst over stroma regions possessing a rich subepithelial vascular supply and high nutrient availability.

This content is only available via PDF.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.