There is increasing evidence that the P100 peak of the pattern-reversal visual-evoked potential (VEP-PR) is delayed by drug-induced dopamine antagonism and in Parkinson’s disease. Recent studies have reported that components of the flash-VEP (VEP-F) are delayed by an anticholinergic which does not affect the VEP-PR. The present study found that a single dose of chloφromazine significantly increased the latencies of the VEP-PR and of the VEP-F and increased the VEP-F P2 amplitude. Trihexyphenidyl increased the VEP-PR amplitude but had only minor effects on the VEP-F. There was a tendency for imipramine to increase VEP-F latencies, especially the N3 peak, but had no effect on the VEP-PR. Both VEPs were unaffected by diazepam. These VEP findings add further support to the role of dopamine in the human visual system. Possible reasons are advanced for the failure of trihexyphenidyl to cause previously reported VEP changes associated with hyoscine hydrobromide. Several important issues need to be addressed by future research.

Keywords:
Visual-evoked potentials, Diazepam, Chlorpromazine, Imipramine, Trihexyphenidyl
This content is only available via PDF.
© 1988 S. Karger AG, Basel
1988
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.