Hypoxia/ischaemia is known to trigger neuronal death, but the role of neuronal nitric oxide synthase (nNOS) in this process is controversial. Nitric oxide (NO) inhibits cytochrome oxidase in competition with oxygen. We tested whether NO derived from nNOS synergises with hypoxia to induce neuronal death by inhibiting mitochondrial cytochrome oxidase. Sixteen hours of hypoxia (2% oxygen) plus deo...

The enzymes aldehyde oxidase and xanthine oxidase catalyze the oxidation of a wide range of N-heterocycles and aldehydes. These enzymes are widely known for their role in the metabolism of N-heterocyclic xenobiotics where they provide a protective barrier by aiding in the detoxification of ingested nitrogen-containing heterocycles. Isovanillin has been shown to inhibit the metabolism of aromati...

flavonoids could serve as potent inhibitors of xanthine oxidase (xo). in the present study, the effects of ruta graveolens l. extract and its major isolated flavonoids, quercetin and rutin, on guinea pig liver xo have been investigated. the inhibitory effects of r. graveolens, quercetin and its glycoside form, rutin, were assayed spectrophotometrically. r. graveolens extract showed moderate inh...

BACKGROUND/AIMS Homovanillamine is a biogenic amine that it is catalyzed to homovanillyl aldehyde by monoamine oxidase A and B, but the oxidation of its aldehyde to the acid derivative is usually ascribed to aldehyde dehydrogenase and a potential contribution of aldehyde oxidase and xanthine oxidase is usually ignored. METHODS The present investigation examines the metabolism of homovanillami...

Apocynin has been used as an efficient inhibitor of the NADPH oxidase complex in experimental studies. NADPH oxidase was originally identified immune cells as playing an important microbicidal role. In cerebral ischemia, inflammation is increasingly being recognized as contributing negatively to neurological outcome, with NADPH-oxidase as an important source of superoxide. Recently, several for...

In their studies of the oxidation of adrenalin and other amines by amine oxidase preparations, Blaschko, Richter, and Schlossmann (1) found that l-ephedrine, triethylamine, triisoamylamine, and dl-1-hydroxy-2-hydrindeneamine are not only not oxidized, but inhibit the action of the enzyme upon isoamylamine. The conclusion was drawn that this inhibition was of the competitive type, because some d...

Tang and Bonner (16) have described an indoleacetic acid (IAA) oxidase system in pea epicotyls, and also an IAA oxidase inhibitor (17). These findings have been confirmed and extended by others (5-8, 18) and an IAA oxidase has been found in several plants, including beans (18) and pineapple leaf tissue (9). The presence of an inhibitor of IAA oxidation has not previously been shown in the pinea...

      Flavonoids could serve as potent inhibitors of xanthine oxidase (XO). In the present study, the effects of Ruta graveolens L. extract and its major isolated flavonoids, quercetin and rutin, on guinea pig liver XO have been investigated. The inhibitory effects of R. graveolens, quercetin and its glycoside form, rutin, were assayed spectrophotometrically. R. graveolens...