Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.3.5.1 (succinate dehydrogenase)
8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The present study was designed to determine whether naftidrofuryl oxalate exerts a possible therapeutic effect on brain energy metabolism impaired by microsphere-induced cerebral embolism in vitro. 2. Injection of microspheres into the right carotid canal resulted in a decrease in tissue high-energy phosphates both in the right and left hemispheres, and an increase in tissue lactate in the right hemisphere, on the 3rd and the 5th day after the embolism. The embolism also induced a marked reduction in mitochondrial oxidative phosphorylation ability and succinate dehydrogenase activity. The results suggest that severe ischaemia was induced in the brain by the microsphere administration. 3. Treatment of microsphere-injected rats with naftidrofuryl oxalate (15 mg kg-1) for 3 or 5 days elicited a significant recovery of tissue high-energy phosphate and lactate levels. The recovery was associated with a significant restoration of mitochondrial succinate dehydrogenase activity on the both days and of mitochondrial oxidative phosphorylation rate on the 5th day. 4. The results suggest that naftidrofuryl oxalate is beneficial in the recovery of cerebral energy metabolism impaired by microsphere-induced cerebral ischaemia, presumably through a mechanism involving its direct effect on the cerebral mitochondrial enzyme activities.
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PMID:Possible therapeutic effect of naftidrofuryl oxalate on brain energy metabolism after microsphere-induced cerebral embolism. 281 26

A lattice of high oxidative metabolic activity occurs in the intermediate gray layer of the human, monkey, and cat superior colliculus. It is composed of a matrix of high enzyme activity that surrounds pale islands or bands of lower activity. In the human the pale bands are 300-400 micron wide while in the smaller colliculi of the monkey and cat they are 100-200 micron wide. The lattice was demonstrated by studying either cytochrome oxidase or succinate dehydrogenase. In the cat and monkey the lattice occurs at the same depth as the lattice of intense acetylcholinesterase activity, but the two lattices are not in spatial register. In the human the lattice of high oxidative metabolic activity is in the middle of the intermediate gray layer, whereas the lattice of intensely stained cholinesterase activity is at the base of this layer, but again the two lattices are not in spatial register. However, in the middle of the intermediate gray layer of the human, there are elongated islands and bands of very low acetylcholinesterase activity that coincide with the pale islands and bands of low cytochrome oxidase activity. An additional lattice of high enzyme activity occurs based on the enzyme nicotinamide dinucleotide phosphate (reduced form)-diaphorase. This lattice is prominent in the cat, occurs more faintly in the monkey, but did not appear to be present in the human. In the intermediate gray layer it had a high degree of overlap with the acetylcholinesterase lattice. The lattice of high oxidative metabolism contains loosely knit clusters of large multipolar cells containing high cytochrome oxidase activity and these cells do not occur in the pale islands. By contrast the cell bodies in the intermediate gray layer that contain either acetylcholinesterase or the diaphorase occur both between and within the patches of corresponding, high enzyme activity. It is suggested that the acetylcholinesterase and diaphorase lattices are mainly associated with afferent fibers while the lattice of high oxidative metabolism is mainly associated with intrinsic cells. The lattices occur in all mammals studied to date and appear to represent a fundamental principle in the organization of the mammalian colliculus. It is concluded that the lattices will provide a useful basis for further studies of the relationship between the many afferent and efferent modules thought to exist in this structure.
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PMID:Lattices of high histochemical activity occur in the human, monkey, and cat superior colliculus. 284 Jun 1

Renal tubular lesions induced in male rats by two different carcinogens, N-nitrosomorpholine (NNM) and N-ethyl-N-hydroxyethylnitrosamine (EHEN), using a limited exposure "stop" protocol were investigated histochemically to demonstrate phenotypic cellular changes. The parameters measured included basophilia, glycogen content and the activity of the enzymes glucose-6-phosphatase (G6PASE), glycogen synthetase (SYN), glycogen phosphorylase (PHO), glucose-6-phosphate dehydrogenase (G6PDH), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), succinate dehydrogenase (SDH), alkaline phosphatase (ALP), acid phosphatase (ACP) and gamma-glutamyl transpeptidase (gamma-GT). The lesions observed were predominantly of either basophilic or oncocytic types. In each case, tubular lesions (altered tubules) appeared to give rise to epithelial tumors (epitheliomas) with the same cellular phenotype. Basophilic tubules and epitheliomas proved to be strongly positive for GAPDH and G6PDH while demonstrating a reduction or loss of G6PASE, ALP, ACP, gamma-GT, and SDH compared with controls and the surrounding proximal or distal tubules. In addition, large basophilic epitheliomas demonstrated an increase in both SYN and PHO activities. In contrast, most oncocytic tubules and oncocytomas characterized by abundant densely granular cytoplasm showed a reduction in the activity of G6PDH, but were intensely positive for SDH. However, a few oncocytic lesions demonstrated a decrease in both SDH and G6PDH activity. Rarely, decreased SDH and elevated G6PDH activities were observed in altered tubules resembling oncocytic tubules. It remains to be clarified whether these tubules represent a variation of the oncocytic lesions or, perhaps, another type of tubular lesion. The results indicate that basophilic and oncocytic epithelial tumors differ in their cytochemical pattern and histogenesis. In line with earlier suggestions, the basophilic tumors apparently originate from the proximal renal tubules, while the oncocytomas develop from the distal parts of the nephron. The basophilic tumors are characterized by an increased pentose phosphate pathway and glycolysis, with a corresponding reduction in mitochondrial respiration. However, the majority of the oncocytomas show an increased activity of the mitochondrial enzyme SDH, and a marked decrease in the activity of the key enzyme of the pentose phosphate pathway.
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PMID:Correlative histochemical studies on preneoplastic and neoplastic lesions in the kidney of rats treated with nitrosamines. 287 45

Crude synaptic membranes isolated from calf brain cortex were subjected to an aqueous two-phase system and the partition of the various membrane constituents and activities between the phases were studied. These constituents were phosphate, cholesterol and protein. The activities measured were acetyl-cholinesterase, succinate dehydrogenase, 2',3'-cyclicnucleotide-3'-phosphohydrolase and stereospecific opiate-binding. The successful fractionation of the membranes was achieved by the use of an aqueous two-phase system in a counter-current distribution process. A ligand bound to poly(ethylene glycol) with an affinity for opiate receptors was synthesized by reacting 6-aminonaloxone with tresylpoly(ethylene glycol). The ligand-polymer was used to extract membrane-bound opiate receptors into the upper, poly(ethylene glycol)-rich phase. This use of affinity partitioning resulted in membrane fractions with a 3-4 fold higher ability to bind stereospecifically etorphine than the original preparations of synaptic membranes.
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PMID:Affinity partitioning and centrifugal counter-current distribution of membrane-bound opiate receptors using naloxone-poly(ethylene glycol). 299 69

A large-scale preparation of the two-subunit protein complex (QPs) that converts succinate dehydrogenase into succinate-ubiquinone reductase from cytochrome b-c1 particles is achieved by a procedure involving Triton X-100 solubilization and calcium phosphate column chromatography at different pH values. The isolated two-subunit QPs contains 25 nmol of cytochrome b560/mg of protein and is able to reconstitute with soluble succinate dehydrogenase to form a TTFA-sensitive succinate-ubiquinone reductase. The maximum reconstitutive activity is 100 mumol of succinate oxidized per min per mg of QPs protein at 23 degrees C. Although cytochrome b560 in isolated QPs is not succinate reducible and its dithionite reduced form is reactive to carbon monoxide, cytochrome b560 is shown to be physically associated with succinate dehydrogenase by the following observations. The dithionite reduced form of cytochrome b560 in isolated QPs has a symmetrical alpha-absorption peak, which upon reconstitution with succinate dehydrogenase becomes slightly broadened and shows a shoulder at around 553 nm, identical to that of cytochrome b560 in succinate-ubiquinone reductase. Upon addition of succinate dehydrogenase to QPs, about 50% of the reduced form of cytochrome b560 in the QPs becomes insensitive to carbon monoxide treatment. The redox potential of cytochrome b560 in QPs is -144 mV which is higher than that of cytochrome b560 in succinate-ubiquinone reductase (-185 mV). Upon addition of succinate dehydrogenase, the redox potential of about 46% of the cytochrome b560 in QPs preparation becomes identical to that of cytochrome b560 in succinate-ubiquinone reductase. Cytochrome b560 in the QPs preparation shows two epr signals, g = 3.07 and g = 2.92, whereas cytochrome b560 in succinate-ubiquinone reductase exhibits only one epr signal at g = 3.46. When QPs is reconstituted with succinate dehydrogenase to form succinate-ubiquinone reductase, the g = 3.46 epr signal reappears at the expense of the g = 3.07 signal. Based on epr measurement at liquid helium temperature, about 18% of the total cytochrome b in the isolated active succinate-cytochrome c reductase is cytochrome b560, indicating that cytochrome b560 is indeed a unique cytochrome b and not a denatured product of cytochrome b562 or b565.
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PMID:Properties of bovine heart mitochondrial cytochrome b560. 302 80

Within the uterine glands, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the activities of G-6-PDH, 6-PGDH, and cytochrome oxidase increase within secreting cells during the 2nd half of pregnancy. The activities of the other enzymes remained almost unchanged during the period of investigation. The description of our results distinguishes between gland neck, middle, and distal part of the secretory unit, respectively. In general, the enzyme activities are similar within the middle and distal gland segments, but lower in the epithelia of the neck region. The activity of dehydrogenases was medium to intensive within the middle and distal gland segments, but only low to medium within the neck portion. Of the hydrolases, the acid phosphatase, ATPase, leucine aminopeptidase, and beta-galactosidase demonstrated an intensive activity within activity secreting cells. The enzyme activities of the gland epithelia are compared with these of the uterine surface epithelia and the histochemical results are discussed in context with their significance in histiotrophic nutrition.
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PMID:[Enzyme histochemistry of the pig placenta. III. Histotopics of enzymes in the uterine epithelium]. 309 49

Male albino mice were pair-fed a torula yeast-based selenium-deficient (Se-) diet containing 10 ppb selenium for 4 months, while a control group (Se+) received a similar diet supplemented with 330 ppb selenium as Na2SeO3. In addition to previously observed modulations of drug-metabolizing enzymes (Reiter, R. and Wendel, A. (1985) Biochem. Pharmacol. 34, 2287-2290), an increase of 6-phosphogluconate dehydrogenase activity and succinate dehydrogenase activity in liver by about 60% was found. In vivo, an increased 14CO2 exhalation from a tracer dose of glucose either labeled in the C-1- or C-6 position was observed in selenium-deficient mice. However, no difference in the total CO2 exhalation of Se(-)- as compared to Se+-mice was detectable. In line with the assumption that Se(-)-mice have an increased glucose turnover, Se(-)-mice exhibited a greater glucose tolerance when treated with an oral glucose load of 2.5 mg glucose/kg body weight. Also, the Se(-)-mice had a lower blood glucose level as compared to Se+-controls (89 +/- 3 versus 110 +/- 12 mg glucose/100 ml blood). Further in vitro experiments with red blood cells from Se(-)-mice showed that erythrocytes did not contribute to an increased CO2 formation from glucose via the pentose phosphate shunt. No significant differences between Se(-)- and Se+-animals were found in the profile of urinary metabolites, including ketone bodies and nitrogen excretion. These findings suggest a hitherto unknown involvement of selenium in specific regulatory sites of intermediary metabolism.
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PMID:Alterations in the intermediary metabolism of selenium-deficient mice. 311 95

Muscle biopsies from six horses with clinical histories of muscle atrophy, muscle tremors, myopathic symptoms, unsteadiness of pelvic limbs and progressive ataxia were examined. Muscle biopsies were studied with enzyme histochemical techniques to evaluate the diagnostic values of these methods in cases suspected of suffering from neuromuscular disorders. Hypertrophy, atrophy, fibre splitting, waxy degeneration, phagocytosis and necrosis were seen in haematoxylin eosin stained sections of the different cases. Fibre type predominance and fibre type grouping were seen in the calcium ion stimulated myosine ATP-ase (Ca-ATP-ase) stained sections of some cases. 'Moth-eaten fibres' were demonstrated in three cases by staining with NADH: nitro blue tetrazolium oxidoreductase (NADH-TR), succinate dehydrogenase (SDH), NADH dependent malate dehydrogenase, cytochrome c oxidase and by lactate dehydrogenase. The catabolic enzymes, acid phosphatase (ACP) and 5'-nucleotidase were active in cases with fibre phagocytosis. The oxidative part of the pentose phosphate pathway in myopathic tissue seemed to be important in three cases, demonstrated by the increased activity of glucose-6-phosphate dehydrogenase (GPDH) and 6-phosphogluconate dehydrogenase (PGDH). The important feature of diseased horse muscle was that the pathohistochemical changes were exactly the same as in diseased skeletal muscles of humans. The application of tissue saving enzyme histochemical techniques can be recommended in the study of muscle tissue from horses suffering from suspected neuromuscular disorders.
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PMID:Enzyme histochemistry on muscle biopsies as an aid in the diagnosis of diseases of the equine neuromuscular system: a study of six cases. 336 6

Changes in carbohydrate metabolism were studied in midgut gland, muscle, and gill tissues of marine prawn Penaeus indicus exposed to a sublethal concentration (0.3 ppm) of phosphamidon. A significant decrease in glycogen and pyruvate and an increase in lactate content were observed in all phosphamidon-exposed prawn tissues after 96 hr. An increase in phosphorylase a and aldolase activity levels suggested the increased formation of triose sugars during phosphamidon toxicity. LDH activity was considerably decreased and an increment in lactate content was observed which indicates reduced mobilization of pyruvate into the citric acid cycle. Glucose-6-phosphate dehydrogenase activity was considerably increased, suggesting the enhanced oxidation of glucose in the hexose monophosphate shunt pathway. Krebs cycle enzymes such as NAD-isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase were found to be decreased, suggesting the impairment in mitochondrial oxidative metabolism due to the acute toxic impact of phosphamidon. Cytochrome-c oxidase and Mg2+ ATPase activity levels were also decreased considerably, suggesting impaired energy synthesis and breakdown during phosphamidon toxicity, as a result of reduced oxidation of glucose aerobically. The increase in acid and alkaline phosphatase activities indicates the enhanced breakdown of phosphate to release energy in view of inhibiton or impairment in the ATPase system during phosphamidon-induced stress. These results suggest that phosphamidon has a profound effect on the oxidative metabolism of prawn which results in the triggering of compensatory metabolic pathways for survivability.
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PMID:Modulation of carbohydrate metabolism in the selected tissues of marine prawn, Penaeus indicus (H. Milne Edwards), under phosphamidon-induced stress. 337 38

Lipid composition of plasma membranes from luteal cells was examined to determine whether changes in this organelle occur during regression and maintenance of the corpus luteum in nonpregnant (NP) and pregnant (P) ewes, respectively. Forty ewes were assigned to be killed on Day 13 or 15 of the estrous cycle (D13-NP and D15-NP) or pregnancy (D13-P and D15-P). Purification of luteal plasma membranes on discontinuous sucrose gradients yielded two fractions, designated F1 and F2, that exhibited the greatest enrichment of 5'-nucleotidase activity (five- and fourfold, respectively) over that of the homogenate. These fractions also yielded the lowest contamination by endoplasmic reticulum as represented by nicotinamide adenine dinucleotide phosphate (NADPH) cytochrome C reductase activity and mitochondrial membranes as indicated by succinate dehydrogenase activity. Predominant phospholipids identified in membranes obtained from all groups were phosphatidylcholine (PC, 48.9 +/- 0.6% of total phospholipid), phosphatidylethanolamine (PE, 33.3 +/- 0.4%), sphingomyelin (SPH, 9.7 +/- 0.3%), phosphatidylserine (PS, 3.5 +/- 0.2%), and phosphatidylinositol (PI, 4.0 +/- 0.5%). No changes in microgram phospholipid/mg membrane protein were observed for any luteal phospholipid on D13 and 15 of the estrous cycle or pregnancy. No significant changes in the relative percentages of major fatty acids present in PC (palmitic [16:0], oleic [18:1]), PE (stearic [18:0], 18:1 and arachidonic [20:4]), or PS (18:0, 18:1, docosatetraenoic [22:4]), nor in the ratios of unsaturated (U) to saturated (S) fatty acids in these phospholipids were observed. Significant differences in unsaturated fatty acids of chain length greater than 20 carbons present in minor quantities in PC, PE, and PS were detected between NP and P ewes as well as between days within reproductive stage. The profile of major fatty acids present in PI revealed decreases in 18:0 and 20:4 in D15-NP and increases in 22:4 and docosapentaenoic acid (22:5) in luteal membranes of both D13- and D15-NP ewes relative to the levels of these fatty acids in PI of corresponding groups of pregnant ewes. There was a general trend for 20:4 levels of PC and PI in membranes of D15-NP ewes to be inversely related to those of D15-P ewes. Collectively, these changes were reflected by an increased U:S fatty acid ratio in luteal membrane PI during the estrous cycle. Specific binding of [125I] iodo-human chorionic gonadotropin to luteal plasma membranes from NP and P ewes on D13 and 15 (6/group) revealed similar affinities and concentrations of unoccupied luteinizing hormone (LH) receptors.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Characterization of plasma membrane lipids and luteinizing hormone receptors of ovine corpora lutea during luteolysis and early pregnancy. 340 35


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