Quick Search:

uzh logo
Browse by:
bullet
bullet
bullet
bullet

Zurich Open Repository and Archive

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-13023

Schildknecht, S; van der Loo, B; Weber, K; Tiefenthaler, K; Daiber, A; Bachschmid, M M (2008). Endogenous peroxynitrite modulates PGHS-1–dependent thromboxane A2 formation and aggregation in human platelets. Free Radical Biology and Medicine, 45(4):512-520.

[img]
Preview
Accepted Version
PDF
2MB

View at publisher

Abstract

Aggregation of activated platelets is considerably mediated by the autocrine action of thromboxane A2 (TxA2) which is formed in a prostaglandin endoperoxide H2 synthase-1 (PGHS-1 or COX-1)-dependent manner. The activity of PGHS-1 can be stimulated by peroxides, an effect termed "peroxide tone", that renders PGHS-1 the key regulatory enzyme in the formation of TxA2. Activated platelets release nitric oxide (*NO) and superoxide (O*2) but their interactions with the prostanoid pathway have been controversially discussed in platelet physiology and pathophysiology. The current study demonstrates that endogenously formed peroxynitrite at nanomolar concentrations, originating from the interaction of *NO and *O2, potently activated PGHS-1, which parallels TxA2 formation and aggregation in human platelets. Inhibition of the endogenous formation of either *NO or O*2 resulted in a concentration-dependent decline of PGHS-1 activity, TxA2 release, and aggregation. The concept of peroxynitrite as modulator of TxA2 formation and aggregation explains the interaction of *NO and O*2 with the PGHS pathway and suggests a mechanism by which antioxidants can regulate PGHS-1-dependent platelet aggregation. This may provide a molecular explanation for the clinically observed hyperreactivity of platelets in high-risk patients and serve as a basis for novel therapeutic interventions.

Citations

17 citations in Web of Science®
18 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

121 downloads since deposited on 09 Feb 2009
54 downloads since 12 months

Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > University Hospital Zurich > Clinic for Cardiology
DDC:610 Medicine & health
Language:English
Date:14 August 2008
Deposited On:09 Feb 2009 10:51
Last Modified:28 Nov 2013 00:28
Publisher:Elsevier
ISSN:0891-5849
Publisher DOI:10.1016/j.freeradbiomed.2008.04.042
PubMed ID:18514074

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page