An experimental model system, consisting of single isolated smooth muscle cells from the rat basilar artery, was developed to study the effects of spasmogens thought to play a role in the pathophysiology of cerebral vasospasm following subarachnoid hemorrhage. In this study, the effects of bilirubin and oxyhemoglobin were compared. Isolated cells were studied under phase contrast optics and with the whole-cell patch clamp technique. Cells exposed to saturated solutions of bilirubin for up to 11 h exhibited only a small degree of contraction which was not significantly different from that observed in similarly treated control cells. In contrast, oxyhemoglobin (1–10 µM) caused an increase in calcium-activated potassium currents, cell contraction, membrane blebbing and an irreversible and precipitous decline in membrane resistance within 5 min. While these experiments do not entirely rule out a role for bilirubin in cerebral vasospasm, they do suggest that oxyhemoglobin is much more likely to be important.

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.