Regional brain concentrations of corticotropin-releasing factor (CRF) exhibited marked differences in a number of regions depending upon the time of day rats were sacrificed. When compared with animals killed at 09.00 h, CRF concentrations at 15.30 h were elevated in the median eminence, hypothalamus minus median eminence, preoptic area/suprachiasmatic nucleus, bed nucleus of the stria terminalis, septum, frontal/parietal cortex, cerebellum, cingulate cortex, locus ceruleus and the nucleus of the solitary tract. Animals that received 7 days of continuous corticosterone supplementation via osmotic minipump either did not exhibit an afternoon rise in CRF concentrations (median eminence, cingulate cortex and locus ceruleus) or exhibited significantly attenuated afternoon increases in CRF concentrations (hypothalamus minus median eminence). In rats killed at 09.00 h, corticosterone reduced CRF concentrations in the median eminence. Chronic corticosterone exposure did not affect CRF concentrations in any of the extrahypothalamic brain regions studied in rats killed at 09.00 h. These results suggest that a number of CRF-containing neurons in both hypothalamic and extrahypothalamic brain regions presumably undergo diurnal changes in their activity as evidenced by changes in CRF concentrations. Furthermore, chronic corticosterone supplementation can alter these changes, particularly those in the endocrine hypothalamus.

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.