The purpose of this study was to characterize the changes in noradrenergic blood pressure regulation and the causes of this dysregulation in patients with histologically proven primary hyperparathyroidism before and after parathyroidectomy. In untreated hypertensive patients with primary hyperparathyroidism slightly higher plasma levels of norepinephrine, enhanced cardiovascular reactivity to norepinephrine (p < 0.05) and increased cytosolic free calcium concentration in platelets (p < 0.05) were found. Parathyroidectomy resulted in the correction of noradrenergic blood pressure dysregulation and in the reduction of cytosolic free calcium and led to normotension. In vitro incubation of platelets from normal subjects with heterologous plasma ultrafiltrates from either hypertensive patients with primary hyperparathyroidism or normotensive uremic patients with secondary hyperparathyroidism led to raised platelet calcium in primary hyperparathyroidism but not in secondary hyperparathyroidism, although in both conditions intact parathormone levels were elevated equally. Furthermore, when platelets of normotensive subjects were preincubated with commercially available parathormone, no effect on resting platelet cytosolic calcium was observed. Our results suggest that hypertension in primary hyperparathyroidism may be caused in part by noradrenergic blood pressure dysregulation and seems to be causally linked to the secretion of a parathyroid hypertensive factor, which increases cytosolic calcium and alters vascular tone and reactivity.

Keywords:
Sympathetic nervous system, Cytosolic calcium, Hypertension, Primary hyperparathyroidism
This content is only available via PDF.
© 1997 S. Karger AG, Basel
1997
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.