BACKGROUND The production of peroxynitrite, an extremely potent oxidant, is increased in inflammatory lung disease. It is therefore important to measure antioxidant activity against peroxynitrite in epithelial lining fluid to examine the physiological effects of peroxynitrite in the airways of patients with asthma. This study was designed to determine whether peroxynitrite inhibitory activity i...

Peroxynitrite, a representative of reactive nitrogen species, plays important roles in the physiological and pathological processes of many oxidative stress-related diseases. It is generated from the reaction of nitric oxide (NO) and superoxide (O2·-) and is far more active than its precursors. Peroxynitrite can be further decomposed into other cytotoxic reactive species. Peroxynitrite and its ...

Nitric oxide is an endogenous autacoid produced primarily by the vascular endothelium. Under basal conditions, nitric oxide undergoes a rapid biradical reaction with superoxide anions to form peroxynitrite. This reaction, and hence the formation of peroxynitrite is augmented in inflammatory-like conditions such as ischemia-reperfusion injury when both substrates are present in high concentratio...

The treatment of erythrocyte membranes with peroxynitrite (ONOO-), a cytotoxic species formed in vivo by the almost completely diffusion controlled reaction of nitric oxide (NO*) and the superoxide anion (O2*-), led to the loss of the EPR signal of the nitroxide radical 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO). The decrease in the TEMPO EPR signal was peroxynitrite concentration dependent ...

BACKGROUND Peroxynitrite is a cytotoxic oxidant formed from nitric oxide (NO) and superoxide. Tyrosine nitration, a footprint of peroxynitrite, has been demonstrated in the pancreatic islets as well as in the cardiovascular system of diabetic subjects. Delineation of the pathogenetic role of peroxynitrite in disease conditions requires the use of potent, in vivo active peroxynitrite decompositi...

In septic shock excessive nitric oxide and superoxide are produced, thus generating peroxynitrite. This study investigates whether and how intravasal peroxynitrite causes lung dysfunction. To generate peroxynitrite, isolated and ventilated rat lungs were perfused blood-free in a pressure-constant, recirculating mode with hypoxanthine/xanthine oxidase plus sodium nitroprusside. Airway and vascul...

Peroxynitrite is the product of the diffusion-controlled termination reaction between two radicals, nitric oxide and superoxide and is a strong oxidant and nitrating intermediate. Critical biomolecules like proteins, lipids and DNA react with peroxynitrite via direct or radical-mediated mechanisms, resulting in alterations in enzyme activities and signaling pathways. The biological consequences...

Peroxynitrite may contribute to oxidative stress involving neurodegeneration in several disorders, including Alzheimer's disease. As with other reactive oxygen species, peroxynitrite might affect neuronal signalling systems, actions that could contribute to adaptive or deleterious cellular outcomes, but such effects have not previously been studied. To address this issue directly, peroxynitrite...

A dansyl derivative (Ds-DAB) was prepared and used as a fluorescent probe for peroxynitrite (ONOO(-)) detection. The results showed that the addition of peroxynitrite to the aqueous solution of Ds-DAB would result in obvious fluorescence enhancement. This probe is highly specific for peroxynitrite in aqueous solution, avoiding interference from other reactive oxygen species (ROS) and nitrogen s...

· AIM: To explore that if peroxynitrite induced the expression of inducible nitric oxide synthase (iNOS)via nuclear factor-kappa B(NF-κ B)pathway in retinal pigment epithelial (RPE) cells and the antagonism of cholecystokinin octapeptide-8 (Melatonin , CCK-8) . ·METHODS: RPE cells were obtained from eyes of C57BL/6 mouse and divided into control, peroxynitrite and CCK-8 groups. Control group wa...