Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.8.1.4 (diaphorase)
 2,754 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The individual effects of two putative metabolites of primaquine (5,6-dihydroxyprimaquine and 5,6-dihydroxy-8-aminoquinoline) on the hexose monophosphate shunt (HMS) and on the ATP-dependent proteolytic system which rapidly degrades oxidized erythrocyte protein were measured in intact red blood cells in vitro from two blood donors. In red cells treated with nitrite (1-40 mM) or phenylhydrazine (0.01-10 mM), proteolytic activity was detected only with concentrations (7.5 mM NaNO2 and 0.25 mM phenylhydrazine) causing greater than 15-fold elevation of HMS activity, and glucose-6-phosphate dehydrogenase (G6PD)-deficient (25% of normal activity) red cell suspensions thus treated showed approximately 30% greater proteolysis. G6PD-normal and deficient red cells treated with the primaquine analogs, however, did not experience proteolysis with concentrations (0.25 mM) in excess of those causing 17-fold elevation of HMS activity. Stimulation of the HMS by the primaquine analogs thus appears unrelated to an erythrotoxic oxidative stress. Methylene blue is known to cause an elevation of HMS activity through direct and diaphorase II-dependent oxidation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) which is independent of injurious oxidative stress. It was found that the putative primaquine metabolites also caused direct and diaphorase II-dependent oxidation of NADPH in dilute hemolysate, thus suggesting that the putative primaquine metabolites have a methylene blue-like redox disposition in red blood cells. Results obtained in this study suggest that the hemolytic toxicity of primaquine may be unrelated to processes which lead to oxidative deterioration of red cell protein.
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PMID:Oxidative activity of hydroxylated primaquine analogs. Non-toxicity to glucose-6-phosphate dehydrogenase-deficient human red blood cells in vitro. 375 45

Study of the activity of some myocardial enzymes in sudden death cases with alcoholic cardiomyopathy (ACMP) was made by quantitative histochemical methods. The decrease of dehydrogenase activity of succinate, lactate, beta-hydroxybutyrate, alpha-glycerophosphate and NAD-diaphorase was found in line with the increase of the activity of glucose-6-phosphate dehydrogenase, alcohol dehydrogenase and catalase versus control (myocardium of those who died of trauma). Disorders of major metabolic processes in the myocardium may occasionally lead to electrical instability resulting in ventricular fibrillation and sudden cardiac death. In almost 80% of sudden cardiac deaths in ACMP foci of acute myocardial ischemia are found, that can lead to ventricular fibrillation with lethal outcome.
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PMID:[Histoenzymologic characteristics of the myocardium in sudden death in patients with alcoholic cardiomyopathy]. 380 Jun 78

The biochemical basis for paraquat tolerance was investigated using one of the paraquat-resistant Escherichia coli mutants previously isolated. When grown in the absence of paraquat (PQ2+), the specific activities of glucose-6-phosphate dehydrogenase and NADPH:PQ2+-diaphorase, both required for the expression of PQ2+ toxicity, were comparable in the wild type and the mutant. However, growth in the presence of 1 mM PQ2+ resulted in greater induction of these two enzymes in the wild type than in the mutant. Nevertheless, when the mutant was grown in 50 mM PQ2+, the activities of these two enzymes were comparable to those of the wild type grown in the presence of 1 mM PQ2+. Measurement of cyanide-resistant respiration, an indication of intracellular superoxide generation, showed that the intracellular flux of superoxide mediated by subsaturating concentrations of paraquat was significantly lower in the mutant than in the wild type. Extracellular superoxide formation, as measured by superoxide dismutase-inhibitable cytochrome c reduction, was higher in the wild type than in the mutant whether grown in the absence or the presence of PQ2+. The mutant did not show cross-resistance toward juglone or plumbagin, compounds known to exacerbate superoxide generation. The kinetics of [14C]PQ2+ uptake showed that the wild type accumulated PQ2+ against a concentration gradient, whereas the mutant seemed to do so only by facilitated diffusion. The results indicate that the impaired paraquat uptake system in the mutant results in the physiological and biochemical differences observed between the wild type and mutant.
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PMID:Biochemical characterization of a paraquat-tolerant mutant of Escherichia coli. 389 18

Histochemical study of enzymatic activity in the myocardium was performed in sudden cardiac death. Human hearts in which there were no macroscopic and histological focal or diffuse changes served as material. The following enzymes were studied in the anterior or posterior walls of the left ventricle or in the interventricular septum: succinate dehydrogenase, lactate dehydrogenase (LDH), beta-hydroxybutyrate dehydrogenase (OHBDH), alpha-glycerophosphate- and glucose-6-phosphate dehydrogenase, NAD-diaphorase and phosphorylase. Increased activity of OHBDH and LDH was found: 36,0 and 22,6% higher than in trauma and brain hemorrhage that served as control. These alterations seem to be connected with the increase of blood content of fatty acids, and lactate as a response to the catecholamine excess. Foci of an acute ischemia were found in the interventricular septum in 80% of cases in which phosphorylase was revealed. The appearance of the ischemic foci was obviously due to the coronary arteries contraction.
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PMID:[Histoenzymological characteristics of the myocardium in sudden cardiac death]. 405 12

The enzyme pattern of 13 cases of malignant fibrous histiocytoma (MFH) and 11 cases of myxofibrosarcoma (MFS), a malignant myxomatous soft tissue tumor of fibroblastic histiocytic origin, has been studied. 6 of the 13 MFHs were analyzed enzyme histochemically at the light microscopic level and 7 on the ultrastructural level; of the 11 MFSs 9 were analyzed enzyme histochemically at the light microscopic level and 2 on the ultrastructural level. Differences were observed in the subjectively estimated enzyme activity between low grade MFS and high grade MFS and MFH, and also between histiocyte-like and fibroblast-like tumor cells. Generally a strong reaction of oxidoreductase enzymes (NADH2-diaphorase, NADPH2-diaphorase, glucose-6-phosphate dehydrogenase) and hydrolytic enzymes (acid phosphatase and leucine aminopeptidase) was found in the high grade tumors and was usually higher in the histiocyte-like than in the fibroblast-like cells. Ultrastructurally acid phosphatase occurred predominantly in primary and secondary lysosomes and Golgi zones of the histiocyte-like cells. A strong reaction of alkaline phosphatase was found light microscopically in 2 of 5 MFHs and 5 of 9 MFSs. Ultrastructurally alkaline phosphatase was located along the cytoplasmic membrane of predominantly fibroblast-like cells in 3 of 7 MFHs and 1 of 2 MFSs. The results agree with the concept of two main cell types in MFH and MFS, fibroblasts and histiocytes.
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PMID:Enzyme histochemistry of malignant fibroblastic histiocytic tumors. A light and electron microscopic analysis. 608 56

The effect of tris-(2-chloroethyl)-amine (HN-3) on RNA and DNA was investigated spectrophotometrically. The shift in the absorbance spectrum caused by the addition of HN-3 was used to test a variety of compounds for their ability to inhibit RNA alkylation. The effect of HN-3 on the activity of several enzymes was also investigated. The activities of ribonuclease A, desoxyribonuclease I, acetylcholinesterase, diaphorase, glutathione reductase, adenosine desaminase, glyoxalase I, 3-hydroxyacyl-CoA-dehydrogenase, xanthine oxidase, glucose-6-phosphate dehydrogenase, hexokinase and the microsomal N-oxygenation of aniline were not changed by HN-3, whereas the activity of cytochrome-c-reductase exhibited a dose dependent diminution in the presence HN-3. Of 105 compounds tested only 14, namely, sodium thiosulfate, dithioxanthine, thiosalicylic acid, 1,2,4-triazole-5-thiol, 2-thiocytosine, 2-thiohistadine, 2,3-dithiosuccinic acid, thioglycolic acid, 3-mercapto-D-valine,6-amino-2-thiouracil, thionicotine amide, dithiothreitol, sodium sulfite, and ergothioneine prevented the alkylation of RNA. All of them also reacted with HN-3 in absence of RNA. No correlation was found between the reaction constant of the reaction compound:HN-3 in the absence of RNA and the concentration of the compound which inhibited RNA alkylation by 50%. The compounds which were effective in vitro were also tested in mice for their ability to reduce HN-3 toxicity in vivo. Only sodium thiosulfate, d-penicillamine, and dithiosuccinic acid were effective. A 3.9fold increase in the LD50 of HN-3 was achieved in mice treated with sodium thiosulfate 3330 mg/kg i.p., a 1.7fold with 2125 mg dithiosuccinic acid/kg, and a 2fold increase with 2500 mg/kg d-penicillamine. The compound tested was injected i.p. 0.5 to 1 min after the s.c. injection of HN-3.
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PMID:Effect of various compounds on the reaction of tris-(2-chloroethyl)amine with ribonucleic acid in vitro and on its toxicity in mice. 617 33

A histochemical study of the metabolism of rat renal arteries and arterioles. Rat renal arteries and arterioles were examined histochemically to determine their metabolic profiles. Succinate, malate and NAD-isocitrate dehydrogenase, cytochrome oxidase and ubiquinone were assessed to determine aerobic metabolism. Glucose-6-phosphate dehydrogenase and DPN diaphorase were evaluated to determine hexose-monophosphate-shunt activity. Anaerobic metabolism was evaluated via lactate dehydrogenase, and the substrate, glycogen. Gomori's lipase, beta-hydroxybutyrate dehydrogenase and amounts of neutral fat and free fatty acids were assessed as indicators of lipid utilization. Myosin ATPase activity was evaluated as an index of ATP utilization for contraction. Deoxyribonucleic and ribonucleic acids were appraised as indicators of protein synthesis. In general, the oxidative enzymes and myosin ATPase demonstrate considerable activity in renal arteries and arterioles which suggests aerobic metabolism and ATP usage. Renal arteries and arterioles also appear capable of anaerobic metabolism as indicated by strong lactate dehydrogenase reactivity and by the presence of slight to moderate quantities of glycogen, while high levels of glucose-6-phosphate dehydrogenase and moderate amounts of deoxyribonucleic acid suggest a potential for beta-hydroxybutyrate dehydrogenase, minimal lipase activity, and the absence of fatty acids with substantial amounts of neutral fat, indicate limited lipid catabolism.
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PMID:A histochemical study of the metabolism of rat renal arteries and arterioles. 620 11

Oral administration of manganese chloride (25 mg/kg b. w. daily) to monkeys for a period of 18 months produced congestion and marked increase in weight of testis. Histopathologic examination revealed interstitial oedema and degeneration of seminiferous tubules. Activities of succinic dehydrogenase, glucose-6-phosphate dehydrogenase and acid phosphatase were significantly inhibited whereas NADH-diaphorase and alkaline phosphatase activities showed only slight inhibition in seminiferous tubules of treated monkeys. It was concluded that chronic exposure to manganese does not produce sever degenerative changes in the testis earlier than metal induced encephalopathy in primates.
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PMID:Manganese induced testicular changes in monkeys. 624 33

Oxygen and glucose consumption and lactate production of the peritoneal membrane and intra-abdominal adhesions were measured in rats after a single intra-peritoneal colloidal silica injection. Enzyme histochemical studies were made of lactate dehydrogenase, succinate dehydrogenase, NADH2-diaphorase, NADPH2-diaphorase, glucose-6-phosphate dehydrogenase, glutamate dehydrogenase, acid phosphatase, leucylaminopeptidase and alkaline phosphatase in the peritoneal membrane. Anaerobic glycolysis comprises 47% of the total glucose consumption in the the normal peritoneum. Glucose consumption and lactate production of the peritoneal membrane increased sharply in the early phase of silica-induced peritonitis and stayed at a high level for a week indicating an enhanced anerobic metabolism. Oxygen and aerobic glucose consumption increased more slowly than anaerobic glucose consumption and reached their maxima 1 week after silica injection, indicating that the rate of aerobic metabolism is also higher in chemical peritonitis than in the controls. On the other hand, glucose consumption and lactate production increased in a parallel fashion in adhesions and in the peritoneum in the early phase of peritonitis. However, the maximum and later levels were less in adhesions than in the peritoneum. In the enzyme histochemical study high activities of enzymes indicating anaerobic energy metabolism and metabolism via the pentose phosphate shunt were seen in cells of the peritoneal membrane during the early phase of peritonitis. No activity was identified in enzymes indicating aerobic energy metabolism and increased catabolism before the end of the first week.
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PMID:Energy metabolism of the peritoneal membrane in silica-induced peritonitis. A biochemical and enzyme histochemical study. 625 64

Young rats were exposed to 2, 5, 8 and 10 Gy 50 kV local irradiation. The epiphyseal region of the proximal tibia was examined with histopathologic, histochemical and enzyme histochemical methods 1 to 90 days after irradiation. One day after irradiation, a decrease in alkaline phosphatase activity was noted and increased activity was found for acid phosphatase, NADH2-diaphorase and glucose-6-phosphate dehydrogenase, especially after 8 and 10 Gy, but also after 5 Gy. Three days after irradiation, all enzymes showed an increased activity and on day 7 the findings resembled those on day 3. Thirty days after irradiation, a return to normal conditions was observed. The most marked morphologic changes were swelling of cells in the hypertrophic cell zone, disturbed order of cells in the zone of proliferation and an increased number of osteoclasts in the metaphyseal bone. These alterations appeared 1 to 3 days after irradiation and normal morphology was seen on day 30 after 2, 5 and 8 Gy and 90 days after irradiation with 10 Gy.
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PMID:Effect of 50 kV irradiation on enzyme activities of growing rat bone. A histopathologic and enzyme histochemical investigation. 630 36


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