A redox-based mechanism for the neuroprotective and neurodestructive effects of nitric oxide and related nitroso-compounds.
Published
Journal Article
Congeners of nitrogen monoxide (NO) are neuroprotective and neurodestructive. To address this apparent paradox, we considered the effects on neurons of compounds characterized by alternative redox states of NO: nitric oxide (NO.) and nitrosonium ion (NO+). Nitric oxide, generated from NO. donors or synthesized endogenously after NMDA (N-methyl-D-aspartate) receptor activation, can lead to neurotoxicity. Here, we report that NO.- mediated neurotoxicity is engendered, at least in part, by reaction with superoxide anion (O2.-), apparently leading to formation of peroxynitrite (ONOO-), and not by NO. alone. In contrast, the neuroprotective effects of NO result from downregulation of NMDA-receptor activity by reaction with thiol group(s) of the receptor's redox modulatory site. This reaction is not mediated by NO. itself, but occurs under conditions supporting S-nitrosylation of NMDA receptor thiol (reaction or transfer of NO+). Moreover, the redox versatility of NO allows for its interconversion from neuroprotective to neurotoxic species by a change in the ambient redox milieu. The details of this complex redox chemistry of NO may provide a mechanism for harnessing neuroprotective effects and avoiding neurotoxicity in the central nervous system.
Full Text
Duke Authors
Cited Authors
- Lipton, SA; Choi, YB; Pan, ZH; Lei, SZ; Chen, HS; Sucher, NJ; Loscalzo, J; Singel, DJ; Stamler, JS
Published Date
- August 12, 1993
Published In
Volume / Issue
- 364 / 6438
Start / End Page
- 626 - 632
PubMed ID
- 8394509
Pubmed Central ID
- 8394509
International Standard Serial Number (ISSN)
- 0028-0836
Digital Object Identifier (DOI)
- 10.1038/364626a0
Language
- eng
Conference Location
- England