The levels of dynorphin-(1-13), leucine enkephalin, β-endorphin and vasopressin immunoreactivity (ir-DYN, ir-1-ENK, ir-β-END, ir-VP) have been determined in the anterior and in the neurointermediate lobes of the pituitary of rats subjected to a variety of manipulations. Dehydration of rats by 5 days enforced imbibition of a 2% solution of NaCl resulted in a significant decrease in the levels of ir-DYN, ir-l-ENK and ir-VP, but not in those of ir-β-END in the neurointermediate lobe of the pituitary. In contrast, substitution of drinking water by a solution containing 20 μg/ml dexamethasone for 5 days produced a significant increase in the neurointermediate pituitary content of ir-DYN, ir-l-ENK and ir-VP, whereas levels of ir-β-END remained unaffected. This treatment, however, resulted in a significant fall in the ir-β-END content of the adenopituitary without changing levels of ir-DYN in this structure. Adrenalectomy was associated with a significant decrease in the ir-DYN, ir-VP and ir-l-ENK content of the neurointermediate lobe of the pituitary and a pronounced elevation in the ir-β-END but not ir-DYN content of the adenohypophysis. These observations are indicative that the regulation mechanisms of the functional state of particular endorphins differ between the anterior and neurointermediate lobes of the pituitary. The concomitant alterations in levels of ir-DYN, ir-l-ENK and ir-VP detected suggest that a common or similar mechanism of regulation may exist for these peptides. A common biosynthetic origin, however, appears to be unlikely, since Brattleboro rats which are unable to synthesize vasopressin possess unchanged ir-DYN- and ir-1-ENK levels in the pituitary.

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.