Previous studies demonstrated that non-stress pituitary-adrenal function in the rat is suppressed by high but physiological plasma levels of corticosterone. The present investigation was under-taken to determine if stress-induced pituitary-adrenal activity might also be suppressed by physiological levels of corticosterone. The corticosteroid sensitivity of responses to several stress stimuli was first determined, using a relatively low dose of dexamethasone (100 µ g/kg). This dose abolished non-stress pituitary-adrenal function and blocked acute (15 min) corticosterone responses to 1 min ether, 3 min heat, and 1 or 3 min supination, but not those to 3 min ether, immobilization, or cold. In a subsequent experiment, several dexamethasone-sensitive stress responses were studied 2 h after sc injection of 1 mg/kg corticosterone; this dose causes transient elevation of plasma corticosterone levels within the physiological range and complete suppression of non-stress pituitary-adrenal function. The response to 1 min supination but not to 1 min ether or 3 min heat was blocked. These findings suggest that corticosteroid feedback may play an important role in controlling not only non-stress but some stress-induced pituitary-adrenal function in the rat.

Keywords:
ACTH, Corticosterone, Feedback, Dexamethasone, Stress
This content is only available via PDF.
© 1972 S. Karger AG, Basel
1972
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.