1,2-Dihydroxybenzene-3,Sdisulfonic acid (Tiron) has been investigated with regard to oxidation to the o-semiquinone form by both photochemical and enzymatic systems. The formation of the o-semiquinone radical can be recorded at pH 6.8 in the electron spin resonance spectrometer at room temperature. The kinetics of formation and decay of the radical has been determined, since it is relatively st...

Superoxide has been shown to be an important intracellular mediator of actions of angiotensin II. Recently, we found that blockade of angiotensin II type-1 receptors in the rostral ventrolateral medulla (RVLM) abrogated the pressor effect of emotional stress in rabbits. In the present study, we examined the influence of superoxide dismutase mimetics, tempol and tiron, in RVLM on cardiovascular ...

iron is quantitatively retained on an adsorbent made by coprecipitation of 1,2-dihydroxybenzene-3,5-disulfonic acid (tiron) and tetradecyldimethylbenzylammonium choride (tdba) an microcrystalline naphthalene as a slurry or packed in a column, in the ph range 6.0-9.0 from a large volumes of aqueous solutions (up to 200 ml on microcrystalline naphthalene and up to 500 ml of aqueous solutions in t...

BACKGROUND We have recently shown that microinjection of the superoxide dismutase mimetic tempol into the pressor region of the rostral ventrolateral medulla attenuates the cardiovascular response to mental (air-jet) stress in rabbits. In the present study, we examined the influence of tempol on the blood pressure (BP) and heart rate (HR) responses to stress in the key region of the hypothalami...

Reactive oxygen species are important modulators of cerebral vascular tone. Recent evidence, mainly from the aorta, suggests that NAD(P)H oxidase is a major source of vascular superoxide. The goal of the present study was to examine the effects of NADH and NADPH that are commonly used to stimulate NAD(P)H oxidase activity, on superoxide levels and cerebral vascular tone. Basilar arteries and ce...

This study explored the hypothesis that a portion of angiotensin II-induced contractions is dependent on superoxide generation and release of a previously unidentified arachidonic acid metabolite that activates vascular smooth muscle thromboxane receptors. Treatment of rabbit aorta or mesentery artery with the thromboxane receptor antagonist SQ29548 (10 μM) reduced angiotensin II-induced contra...

BACKGROUND Occupational exposure to beryllium may cause Chronic Beryllium Disease (CBD), a lung disorder initiated by an electrostatic interaction with the MHC class II human leukocyte antigen (HLA). Molecular studies have found a significant correlation between the electrostatic potential at the HLA-DP surface and disease susceptibility. CBD can therefore be treated by chelation therapy. In th...