Hyperthermia was induced in ICR mice on day 8.5 of gestation by immersing them in hot water. Control mice were immersed in water at 38°C for 15 min. In dams exposed to 42°C for 12.5–15 min or to 43°C for 7.5–10 min, externally malformed fetuses increased significantly and in a dose-related manner. Anterior neural tube defects (exencephaly, anencephaly, encephalocele, and cranial neural tube defect with facial cleft) were induced most frequently. Embryonic and fetal death and skeletal malformations also increased following heat stress. At intervals after heat exposure, sections of embryonic prosencephalon were prepared for light microscopy. At 2 h after heat stress, mitotic figures disappeared almost completely in embryonic tissues. Mitotic activity was inhibited for at least 3 h. At 6 h, there was a burst of new mitotic activity. Some damaged cells became pyknotic and abnormal cells were encountered in the neuroepithelial tissue after 3–12 h. Thus, neural tube defects in mouse embryos following maternal hyperthermia may result from a temporary cessation of cell proliferation and partial necrosis of the embryonic neuroepithelium.

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.