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PubMed2001

Influence of protein composition on total urinary protein determined by pyrocatechol-violet (UPRO vitros) and pyrogallol red dye binding methods.

Influence of protein composition on total urinary protein assays was evaluated for pyrogallol red-molybdate both with and without sodium dodecyl sulfate (SDS) and pyrocatechol violet-molybdate complex (UPRO) techniques. Using mixtures of albumin and gamma-globulins (n = 8; albumin/globulin ratio, 0 to 10), mean recoveries were 79, 77, and 81% for pyrogallol red, pyrogallol red-SDS, and UPRO, respectively. Using diluted myeloma sera (n = 26; A/G ratio, 0.39 to 2.35), mean recovery by the UPRO method was 115% (vs. 63% for pyrogallol red and 83% pyrogallol red-SDS). Results positively correlated with A/G ratio for UPRO (r = 0.69; P < 0.001), pyrogallol red (r = 0.48; P < 0.05), but not pyrogallol red-SDS (r = 0.191; NS). The difference between UPRO and pyrogallol red assays correlated with the A/G ratio (r = 0.82; P < 0.001). In light chain proteinuria (n = 10), no significant difference (< 15%) was observed between techniques, whereas in glomerular selective proteinuria (n = 10), values were significantly higher with the UPRO assay (2.20 +/- 1.61 vs. 1.43 +/- 1.10 g/L; P < 0.02). Our results support the idea that screening for renal diseases can be performed with UPRO or pyrogallol red assays. However, since A/G ratios may vary with renal disease evolution, follow-up of patients with positive proteinuria should be performed using the same assay, preferably the pyrogallol red-SDS.

Bence Jones Protein↗

PubMed2004

Metabolism of pyrogallol to purpurogallin by human erythrocytic hemoglobin.

The aim of this study was to investigate the oxido-reductive reactions of human hemoglobin with pyrogallol and the metabolism of pyrogallol by the protein, which contains a protoporphyrin IX like cytochrome P-450. Pyrogallol, having three hydroxy groups at the adjacent positions in the benzene ring, oxidized human oxyhemoglobin to methemoglobin and reduced human methemoglobin to oxyhemoglobin. Since superoxide dismutase and catalase inhibited these reactions extensively, active oxygens such as superoxide and hydrogen peroxide were considered to be involved in the oxido-reductive reaction of human hemoglobin by pyrogallol. It was also found that the metabolism of pyrogallol to purpurogallin occurred quickly in human erythrocytes, i.e., when pyrogallol was added to human erythrocyte suspension, it oxidized intracellular hemoglobin and produced purpurogallin. The metabolism of pyrogallol to purpurogallin was explained by the pyrogallol oxidation with superoxide and hydrogen peroxide produced during the oxido-reductive reactions of human hemoglobin with pyrogallol. The present results show that human erythrocytes can metabolize pyrogallol, suggesting that the cells may be involved in the metabolism of some drugs in the human body.

Benzocycloheptenes↗

PubMed1988

Pharmacological evidence that endothelium-derived relaxing factor is nitric oxide: use of pyrogallol and superoxide dismutase to study endothelium-dependent and nitric oxide-elicited vascular smooth muscle relaxation.

The principal objective of this study was to elucidate the influence of superoxide anion on both endothelium-dependent arterial relaxation elicited by acetylcholine and endothelium-independent arterial relaxation produced by nitric oxide (NO). Pyrogallol was used to generate superoxide in the oxygenated bathing medium, and superoxide dismutase was used to scavenge superoxide. Pyrogallol caused endothelium-dependent contractions of bovine intrapulmonary arterial and venous smooth muscle after precontraction of muscle by phenylephrine. Acetylcholine- and NO-elicited arterial relaxations were promptly converted to marked contractions upon addition of pyrogallol. Moreover, pyrogallol markedly inhibited the development of arterial relaxant responses to acetylcholine and NO. However, isoproterenol- and glyceryl trinitrate-elicited arterial relaxations were unaffected by pyrogallol. Both pyrogallol and oxyhemoglobin enhanced arterial contractile responsiveness to phenylephrine in an endothelium-dependent manner, whereas indomethacin was without effect. Similarly, both pyrogallol and oxyhemoglobin inhibited acetylcholine- and NO-elicited arterial cyclic GMP accumulation, whereas indomethacin was without effect. Uncontracted arterial rings maintained under tension showed endothelium-dependent contraction and decreased cyclic GMP levels in response to oxyhemoglobin but not pyrogallol. Superoxide dismutase enhanced arterial relaxation and cyclic GMP accumulation in response to both acetylcholine and NO. Using a bioassay superfusion cascade system in which intact perfused artery was the source of endothelium-derived relaxing factor (EDRF) and three endothelium-denuded arterial strips mounted in series served as the detector of EDRF, superfusion of strips with pyrogallol blocked relaxation caused by perfusion of artery with acetylcholine. Superoxide dismutase enhance the relaxations produced by arterial perfusion with acetylcholine and prevented the effects of pyrogallol.

Animals↗

PubMed2000

Effect of antioxidants on pyrogallol-induced delay in gastric emptying in rats.

The effect of a free radical generator pyrogallol on gastric emptying was studied in rats. Pyrogallol at doses of 25, 50, 100 and 150 mg/kg (i.p.) produced dose-dependent inhibition of gastric emptying. Pretreatment with vitamin C (100 and 500 mg/kg, p.o.), and vitamin E (100 and 500 mg/kg, p.o.) significantly reversed the inhibition in gastric emptying caused by pyrogallol 100 mg/kg. However, the combination of vitamin C and vitamin E (100 mg/kg) produced synergistic effect. Glutathione (100 mg/kg i.v.) 5-min pretreatment also reversed the inhibition of gastric emptying caused by pyrogallol 100 mg/kg. Ondansetron (3 mg/kg, p.o.) significantly reversed the pyrogallol effect. The effect of pyrogallol on malondialdehyde (MDA) levels and 5-HT levels in the stomach tissue was also studied. Pyrogallol at a dose of 100 mg/kg, i.p., significantly increased MDA levels and 5-HT levels in the stomach. Pretreatment with a combination of vitamin C and vitamin E (100 mg/kg, p.o.) and glutathione (100 mg/kg, i.v.) significantly ameliorated the rise in stomach tissue MDA caused by pyrogallol but had no significant effect on the rise in 5-HT levels caused by pyrogallol. The effect of different doses of 5-HT on gastric emptying was also studied. 5-HT had a differential effect on gastric emptying. The low and high doses (0.1, 0.3 and 30 mg/kg, i.p.) significantly inhibited the gastric emptying while doses ranging from 1 to 10 mg/kg, i.p., had no significant effect on the gastric emptying. The pretreatment with antioxidants, combination of vitamin C and vitamin E (100 mg/kg each, p.o.) and glutathione (100 mg/kg, i. v.) had no effect on the 5-HT (0.3 mg/kg, i.p.)-induced delay in gastric emptying. The result indicate the role of free radicals gastric emptying, and antioxidants may be of potential therapeutic value in disease conditions where free radicals are known to be released and the gastrointestinal effects are observed as symptoms or side effects of drug therapy.

Animals↗

PubMed1999

Towards the reaction mechanism of pyrogallol-phloroglucinol transhydroxylase of Pelobacter acidigallici.

Conversion of pyrogallol to phloroglucinol was studied with the molybdenum enzyme transhydroxylase of the strictly anaerobic fermenting bacterium Pelobacter acidigallici. Transhydroxylation experiments in H218O revealed that none of the hydroxyl groups of phloroglucinol was derived from water, confirming the concept that this enzyme transfers a hydroxyl group from the cosubstrate 1,2,3, 5-tetrahydroxybenzene (tetrahydroxybenzene) to the acceptor pyrogallol, and simultaneously regenerates the cosubstrate. This concept requires a reaction which synthesizes the cofactor de novo to maintain a sufficiently high intracellular pool during growth. Some sulfoxides and aromatic N-oxides were found to act as hydroxyl donors to convert pyrogallol to tetrahydroxybenzene. Again, water was not the source of the added hydroxyl groups; the oxides reacted as cosubstrates in a transhydroxylation reaction rather than as true oxidants in a net hydroxylation reaction. No oxidizing agent was found that supported a formation of tetrahydroxybenzene via a net hydroxylation of pyrogallol. However, conversion of pyrogallol to phloroglucinol in the absence of tetrahydroxybenzene was achieved if little pyrogallol and a high amount of enzyme preparation was used which had been pre-exposed to air. Obviously, the enzyme was oxidized by air to form sufficient amounts of tetrahydroxybenzene from pyrogallol to start the reaction. A reaction mechanism is proposed which combines an oxidative hydroxylation with a reductive dehydroxylation via the molybdenum cofactor, and allows the transfer of a hydroxyl group between tetrahydroxybenzene and pyrogallol without involvement of water. With this, the transhydroxylase differs basically from all other hydroxylating molybdenum enzymes which all use water as hydroxyl source.

Bacteria, Anaerobic↗

PubMed2004

The oxygen radical generator pyrogallol impairs cardiomyocyte contractile function via a superoxide and p38 MAP kinase-dependent pathway: protection by anisodamine and tetramethylpyrazine.

Oxygen-derived free radicals have been demonstrated to contribute to the pathogenesis of myocardial dysfunction, although the underlying mechanism remains not fully understood. This study was designed to examine the role of the superoxide generator pyrogallol on cardiac contractile function and possible intervention with herbal medicines anisodamine and tetramethylpyrazine (TMP) on pyrogallol-induced cardiac contractile response. Adult rat ventricular myocytes were isolated and stimulated to contract at 0.5 Hz. Mechanical properties were evaluated using an IonOptix system including peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR(90)), and maximal velocity of shortening/relengthening (+/-dL/dt). A 10-min exposure of pyrogallol (0 to 10(-2) M) did not affect cardiac contractile mechanics. However, longer duration of pyrogallol exposure (1, 3, and 6 h) significantly shortened resting cell length, reduced PS and +/-dL/dt, and prolonged TPS and TR90 in time- and concentration-dependent manners. The pyrogallol (10(-4) M with 6-h incubation)-induced mechanical defects were prevented by the p38 mitogen-activated protein (MAP) kinase inhibitor SB203580 (1 microM) and superoxide dismutase (SOD, 500 U/mL) with the exception that pyrogallol-induced PS depression was unaffected by SOD. Interestingly, incubation of herbal antioxidants anisodamine (10(-7) M) and TMP (10(-7) M) effectively attenuated the pyrogallol-induced cardiac mechanical defects with the exception of PS unaffected by TMP. Our data demonstrate a direct inhibitory effect of pyrogallol on cardiac contraction, probably in a superoxide- and p38 MAP kinase-dependent manner. The antioxidant medicines anisodamine and TMP may be useful in the treatment of oxygen free radical-induced myocardial dysfunction.

Animals↗

PubMed1990

Pyrogallol-to-phloroglucinol conversion and other hydroxyl-transfer reactions catalyzed by cell extracts of Pelobacter acidigallici.

Permeabilized cells and cell extracts of Pelobacter acidigallici catalyzed the conversion of pyrogallol (1,2,3-trihydroxybenzene) to phloroglucinol (1,3,5-trihydroxybenzene) in the presence of 1,2,3,5-tetrahydroxybenzene. Pyrogallol consumption by resting cells stopped after lysis by French press or mild detergent (cetyltrimethylammonium bromide [CTAB]) treatment. Addition of 1,2,3,5-tetrahydroxybenzene to the assay mixture restored pyrogallol consumption and led to stoichiometric phloroglucinol accumulation. The stoichiometry of pyrogallol conversion to phloroglucinol was independent of the amount of tetrahydroxybenzene added. The tetrahydroxybenzene concentration limited the velocity of the transhydroxylation reaction, which reached a maximum at 1.5 mM tetrahydroxybenzene (1 U/mg of protein). Transhydroxylation was shown to be reversible. The equilibrium constant of the reaction was determined, and the free-energy change (delta G degree') of phloroglucinol formation from pyrogallol was calculated to be -15.5 kJ/mol. Permeabilized cells and cell extracts also catalyzed the transfer of hydroxyl moieties between other hydroxylated benzenes. Tetrahydroxybenzene and hydroxyhydroquinone participated as hydroxyl donors and as hydroxyl acceptors in the reaction, whereas pyrogallol, resorcinol, and phloroglucinol were hydroxylated by both donors. A novel mechanism deduced from these data involves intermolecular transfer of the hydroxyl moiety from the cosubstrate (1,2,3,5-tetrahydroxybenzene) to the substrate (pyrogallol), thus forming the product (phloroglucinol) and regenerating the cosubstrate.

Bacteria, Anaerobic↗

PubMedDate not supplied

Pyrogallol poisoning of pigeons caused by acorns.

Green acorns are known to contain high concentrations of pyrogallol. Here, we describe an extended case report of two pigeons found dead with a filled muscular stomach of acorns. The following pathologic findings were observed: irritation of mucosal membranes in the gastrointestinal tract, blackish discolored chyme, hyperemic organs, and general edemas. The muscular stomach (ventriculus) was filled with pieces of acorns, and the abdominal cavity contained bloody aqueous fluid. In order to uncover the cause of death, we determined pyrogallol in liver and kidney of one dead pigeon and in ventriculus contents of both pigeons by gas chromatography/mass spectrometry. A further aim of our study was to compare pathologic findings and pyrogallol concentrations in kidney, liver, and ventriculus of poisoned pigeons with those of healthy pigeons. The pyrogallol concentrations in samples of dead pigeons were 16-1200-fold higher than in control animals fed grass and maize-corn. Altogether, the acorn-filled ventriculus, the pathologic findings, the well nourished state, and the high pyrogallol concentrations in the dead pigeons suggest an acute pyrogallol poisoning by acorn. With respect to controls, we conclude that pyrogallol concentrations of 6 ng/g of kidney, 8 ng/g of liver, and 2 ng/g of gastric content do not affect the health of pigeons.

Animals↗

PubMed2002

The contribution of the pyrogallol moiety to the superoxide radical scavenging activity of flavonoids.

Sixteen flavonoids including flavonols, flavones, flavanonol and catechins, and five aromatic compounds were examined for their ability to scavenge superoxide radical (O2-*) generated enzymatically in a xanthin-xanthinoxidase system and non-enzymatically in a phenazine methosulfate-NADH system. Pyrogallol, gallic acid and its ester, were much more efficient in scavenging O2-* than catechol. The superiority of pyrogallol over catechol in the flavonoidal nucleus is apparent from the much higher O2-* scavenging activity of myricetin and epigallocatechin, which contain 3',4',5'-trihydroxyl substitution in the B-ring, compared to quercetin and epicatechin, which contain 3',4'-dihydroxyl substitution, respectively. The strong O2-* scavenging ability of pyrogallol appears to function even in the A-ring, as in baicalein, and also in the form of a pyrogalloyl ester at the C-3 position in the C-ring, as in epicatechin gallate and epigallocatechin gallate. It can be concluded that the pyrogallol moiety is an active component of flavonoids for displaying high O2-* scavenging activity. Flavonoids and aromatics were also examined to correlate their O2-* scavenging activity with their oxidizability, which was measured on the basis of electrochemical redox potential and the reducing ability of the Cu2+ ion. Aromatics such as pyrogallol, gallic acid and its ester, and flavonoids such as baicalein, epicatechin gallate and epigallocatechin gallate, in which the O2-* scavenging activity is enhanced by the presence of a pyrogallol moiety which does not belong to the B-ring, reduced the correlation between the higher O2-* scavenging activity and the lower redox potential. The O2-* scavenging activity was well correlated with the Cu2+ reducing ability of flavonoids and aromatics.

Copper↗

PubMed2004

[Study on the chemiluminescence (CL) analysis for the determination of pyrogallol in water environment].

The effect of polyhydroxyphenols on the new chemiluminescence (CL) system of isothiocyanatoisoluminol (ITCI) was studied. Pyrogallol was found to enhance the CL obviously, which provided a new CL method for the determination of pyrogallol. Effect of pH, KIO4 and ITCI concentration on the CL intensity of the system was investigated. An intensive interference study of usual ions and screen reagent was also carried out. Under optimum conditions, a linear relationship between pyrogallol and CL intensity was observed in the range of 1.75 x 10(-8) -2.5 x 10(-6) mol x L(-1). The detection limit of pyrogallol was 3.49 x 10(-9) mol x L(-1) (DL = 3 s/r). The relative standard deviation was 5.60% (5 x 10(-7) mol x L(-1) pyrogallol, n = 9). Furthermore, the method has been applied to the detection of pyrogallol in a simulated sample with satisfactory results. The recovery of the method was 94.0%-112.0%.

Fluorescent Dyes↗

PubMed2004

Self-recognition, structure, stability, and guest affinity of pyrogallol[4]arene and resorcin[4]arene capsules in solution.

In the present study, we used diffusion NMR to probe the structures and characteristics of the products obtained from the self-assembly of resorcin[4]arenes 1a and 1b and pyrogallol[4]arenes 2a and 2b in CDCl(3) solutions. It was found that all four molecules self-assemble into hexameric capsules. The hexameric capsules of pyrogallol[4]arenes 2a and 2b were found to be more stable than the capsules of resorcin[4]arenes 1a and 1b in polar media. We also studied the role of water molecules in the self-assembly of the different capsules and found that water molecules are part of the hexameric capsules of resorcin[4]arenes 1a and 1b but not in the capsules of pyrogallol[4]arenes 2a and 2b. It was found that the self-assembly process between the resorcin[4]arenes and pyrogallol[4]arenes proceeds with self-recognition. When mixing two macrocycles of different types in a chloroform solution, no heterohexamers are formed, only the capsule constructed from the same macrocycle is detected. However, when two resorcin[4]arenes (i.e., 1a and 1b) or two pyrogallol[4]arenes (i.e., 2a and 2b) are mixed, heterohexamers are formed over time. In addition, we found that resorcin[4]arenes and pyrogallol[4]arenes differ significantly in their guest affinity. The capsules of 1a and 1b can accommodate both the tertiary alkylamines and their respective ammonium salts, while the capsules of 2a and 2b encapsulate only the neutral tertiary alkylamines.

Journal Article↗

PubMed1994

Induction of emesis in Suncus murinus by pyrogallol, a generator of free radicals.

1. We investigated whether or not pyrogallol, a generator of free radicals, is emetogenic in Suncus murinus, the house musk shrew. Pyrogallol (i.p.) caused dose-dependent emesis in suncus with an ED50 value of 77.3 mg kg-1. At a dose of 128 mg kg-1, all suncus vomited with mean latency of 18.8 +/- 5.2 min and the number of vomiting episodes was 8.6 +/- 2.9. 2. The prophylactic effects of N-(2-mercaptopropionyl)-glycine (MPG), an antioxidant, and tropisetron, a 5-hydroxytryptamine3 (5-HT3) receptor antagonist, were studied. Pyrogallol (128 mg kg-1, i.p.)-induced emesis was prevented by treatment with MPG (i.p.) or tropisetron (s.c.) with ID50 values of 149 mg kg-1 and 117 micrograms kg-1, respectively. 3. Pyrogallol-induced emesis was completely prevented by surgical abdominal vagotomy. 4. The present results indicate that pyrogallol-induced emesis is characteristically very similar to that caused by cisplatin and support the idea that generation of free radicals causes the release of peripheral 5-HT, which stimulates vagal afferent sensory nerves to cause emesis.

Animals↗

PubMed2002

Pyrogallol-induced hepatotoxicity in rats: a model to evaluate antioxidant hepatoprotective agents.

Various hepatic disorders and hepatotoxic agents are associated with increased free radical generation. In the present study, the free radical generator pyrogallol (100 mg/kg i.p.) caused significant hepatic damage. The serum enzymes asparatate aminotransaminase (AST) and alanine aminotransaminase (ALT) increased to 357 +/- 30.7 IU/I and 147.8 +/- 28.4 IU/I, respectively in the pyrogallol-treated group compared with 208.4 +/- 4.1 IU/I and 84.5 +/- 19.5 IU/I, respectively in the control rats. Compared with control rats, the liver tissue in the pyrogallol-treated group showed an increased level of malondialdehyde (MDA) as well as glutathione (GSH). The infiltration of white blood cells into the liver tissue, as seen histologically, further substantiated liver damage. Pretreatment with a standard hepatoprotective drug (silymarin, 100 mg/kg i.p.) afforded significant protection against pyrogallol hepatotoxicity, as evidenced by amelioration of the raised serum markers of hepatic function, markers of oxidative stress and normal liver histology. Thus, pyrogallol-induced hepatotoxicity could be used as an appropriate model to evaluate hepatoprotective agents that have an antioxidant property.

Alanine Transaminase↗

PubMed2000

[Pyrogallol concentrations in rumen content, liver and kidney of cows at pasture].

Pyrogallol (1, 2, 3-trihydroxybenzene), the decomposition product of hydrolysable tannins in oak bark, leaves and acorns, is suspected to be poisonous to animals. The aim of our investigations was to correlate clinical signs and pathological findings with pyrogallol concentrations in organs of poisoned and healthy animals. In a field study, pyrogallol concentrations were determined in liver, kidney, and rumen from seven cattle. In a herd of twelve cows, five animals suffered from hemorrhagic diarrhea, anorexia, weakness, rumen stasis, dyspnoea, and colic symptoms. Death was observed in five cows within five weeks after repeated intake of green acorns and oak leaves. Toxicological analyses of rumen content, liver, and kidney specimens of one cattle confirmed the suspicion of pyrogallol contamination. In this animal, values ranged from 6 to 13 ng pyrogallol per gram specimen. In control cattle, concentrations were clearly lower than in perished cattle. Under antioxidative work-up conditions, detection limit was 0.6 ng/g in rumen content and 1.0 ng/g in liver and kidney, respectively.

Animal Feed↗

PubMed2003

Striatal formation of 6-hydroxydopamine in mice treated with pargyline, pyrogallol and methamphetamine.

Formation of 6-hydroxydopamine (6-OHDA) has been posited in the striatum following methamphetamine treatment and plays a critical role in methamphetamine-induced nigrostriatal dopaminergic toxicity. We used high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) to determine the formation of 6-OHDA by the treatments of methamphetamine combined with pargyline, a monoamine oxidase inhibitor, and pyrogallol, a catechol-O-methyl-transferase inhibitor, in female C57BL/6J mouse striatum. A substantial amount of 6-OHDA (9.9 +/- 0.7 pg/mg wet tissue) was detected in mice treated with pargyline (100 mg/kg) and pyrogallol (25 mg/kg) in combination. Greater striatal 6-OHDA levels were observed in mice treated with combined pargyline, pyrogallol and methamphetamine (50 mg/kg) as compared to mice treated with combined pargyline and pyrogallol. However, mice treated with pargyline and pyragollol in combination followed by one and two doses of methamphetamine exhibited comparable striatal 6-OHDA levels (23.2 +/- 4.3, 27.3 +/- 1.3 pg/mg wet tissue) in our protocol. We conclude that blockade of the primary metabolic pathways of dopamine by inhibiting both monoamine oxidase and catechol-O-methyl-transferase activities is sufficient to induce 6-OHDA formation in the striatum. Acute 6-OHDA accumulation in the striatum can be potentiated by methamphetamine, a potent dopamine releaser, administration following such metabolic inhibitions.

Animals↗

PubMed1999

Effects of pyrogallol, hydroquinone and duroquinone on responses to nitrergic nerve stimulation and NO in the rat anococcygeus muscle.

1. The hypothesis that endogenous superoxide dismutase (SOD) protects the nitrergic transmitter from inactivation by superoxide and that this explains the lack of sensitivity of the transmitter to superoxide generators was tested in the rat isolated anococcygeus muscle. 2. Responses to nitrergic nerve stimulation or to NO were not significantly affected by exogenous SOD or by the Cu/Zn SOD inhibitor diethyldithiocarbamic acid (DETCA). 3. Hydroquinone produced a concentration-dependent reduction of responses to NO with an IC50 of 27 microM, and higher concentrations reduced relaxant responses to nitrergic nerve stimulation with an IC50 of 612 microM. The effects of hydroquinone were only slightly reversed by SOD, so it does not appear to be acting as a superoxide generator. 4. Pyrogallol produced a concentration-dependent reduction in responses to NO with an IC50 value of 39 microM and this effect was reversed by SOD (100-1000 u ml(-1)). Pyrogallol did not affect responses to nitrergic nerve stimulation. Treatment with DETCA did not alter the differentiating action of pyrogallol. 5. Duroquinone produced a concentration-dependent reduction of relaxations to NO with an IC50 value of 240 microM and 100 microM slightly decreased nitrergic relaxations. After treatment with DETCA, duroquinone produced greater reductions of relaxant responses to NO and to nitrergic stimulation, the IC50 values being 8.5 microM for NO and 40 microM for nitrergic nerve stimulation: these reductions were reversed by SOD. 6. The findings do not support the hypothesis that the presence of Cu/Zn SOD explains the greater susceptibility of NO than the nitrergic transmitter to the superoxide generator pyrogallol, but suggest that it may play a role in the effects of duroquinone.

Animals↗

PubMedDate not supplied

Increased carbon disulfide-stimulated chemiluminescence in the pyrogallol-luminol system.

We studied the effect of carbon disulphide (CS2) on the generation of superoxide anion (O2-*) and its chemiluminescence (CL) in the pyrogallol-luminol system. Testing was conducted with the pyrogallol-luminol system to observe the CL dynamic curve of CS2 and the inhibition by superoxide dismutase (SOD) on CL induced by CS2. Compared with the ethanol solvent control, CS2 enhanced the emission intensity of CL and delayed the peak time. There was a significant dose-concentration relationship between CS2 concentrations (10, 40, 80 mg/mL) and CL peak (r = 0.975 p = 0.012) and CS2 concentrations and peak time (r = 0.990, p = 0.005). The CL peak at 80 mg/mL CS2 was higher than that in a background without ethanol. The enhanced CL evoked by CS2 could be inhibited by SOD. The results suggest that CS2 can induce the pyrogallol-luminol system to generate an increased amount of O2-* and delay the CL peak time.

Carbon Disulfide↗

PubMed1996

Pyrogallol red-molybdate: a reversible, metal chelate stain for detection of proteins immobilized on membrane supports.

Certain metal complexes selectively interact with proteins immobilized on solid-phase membrane supports to form brightly colored products. The metal chelates form protein-dye complexes in the presence of metal ions at acidic pH but are eluted from the proteins by immersing membranes in a solution of basic pH that contains other chelating agents. The reversible nature of the protein staining procedure allows for subsequent biochemical analyses, such as immunoblotting, N-terminal and internal protein sequencing. Among the metal complexes evaluated to date, the triazine dye-ferrous complexes (ferene S, ferrozine) and the ferrocyanide-ferric complexes provide the most sensitive detection of proteins immobilized on membranes. While the pyrogallol red-molybdate complex is commonly used in solution-based total protein assays, its utility as a reversible stain for proteins immobilized on membranes has not been reported. Pyrogallol red-molybdate complexes readily stain proteins on nitrocellulose and polyvinyl difluoride membranes with similar sensitivity as ferrozine-ferrous complexes. Analysis of charge-fractionated carrier ampholytes and synthetic polymers of different L-amino acids indicate that binding is prominently via protonated alpha and epsilon-amino side chains. Carbamylation of amino groups in bovine serum albumin substantially diminishes pyrogallol red-molybdate binding to the protein. The stain is reversible, resistant to chemical interference, and compatible with immunoblotting.

Chelating Agents↗