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)

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

In order to elucidate the problem of which cells are involved in calcium transport and to estimate the role of mitochondria in calcium transport in the avian shell gland, the fine structure and the Ca-ATPase, succinate dehydrogenase (SDH) and nicotinamide adenine dinucleotide (NAD+)-dependent isocitrate dehydrogenase (NAD+-ICDH) activity of the shell gland of egg-laying Japanese quails were examined. The surface epithelial cells, consisting of ciliated cells with cilia and microvilli and non-ciliated cells with microvilli, had many large and electron-dense granules. The tubular-gland cells occupied the proprial layer and lacked secretory granules. When an egg was in the shell gland, the well-developed mitochondria of tubular-gland cells characteristically tended to accumulate in the apical cytoplasm, while they were scattered throughout the cytoplasm when an egg was not in the shell gland. Intense Ca-ATPase activity was found on the microvilli of tubular-gland cells, and moderate activity was found on the lateral-cell surface. In the surface epithelial cells, the basolateral cell surface showed moderate enzymatic activity. Both SDH and NAD+-ICDH activity were found in tubular-gland cells when an egg was in the shell gland. These results strongly suggest that calcium for eggshell calcification is actively transported by the tubular-gland (depending on Ca-ATPase activity) and that the mitochondria of gland cells may play an important role in this process as an energy source.
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PMID:Histochemical studies of Ca-ATPase, succinate and NAD+-dependent isocitrate dehydrogenases in the shell gland of laying Japanese quails: with special reference to calcium-transporting cells. 293 10

Using quantitative histochemical techniques, it was determined that the tensor tympani muscle of the cat consists of three muscle fiber types: type 1, type 2A (staining characteristics similar to the type 1 and type 2A muscle fibers found in the control tibialis anterior muscles), and a third unclassified fiber type (type 3) similar to the 2A fiber type except that it had extremely dense alkaline actomyosin adenosine triphosphatase staining (mean transmittance, type 2A = 33.6%; type 3 = 17.3%), as well as dense staining for periodic acid-Schiff, menadione-linked alpha-glycerolphosphate dehydrogenase, nicotinamide-adenine dinucleotide tetrazolium reductase, and succinic dehydrogenase. The type 1 fiber population was smaller in diameter (mean +/- SD, 14 +/- 4 microns) than the type 2A fiber (mean +/- SD, 21 +/- 5 microns) and the type 3 fiber (mean +/- SD, 22 +/- 6 microns) populations. In all muscles, intrafascicular and extrafascicular fat accumulations were found, with the majority being extrafascicular. Calculations indicate that the tendon occupies approximately 41% of the total muscle volume, while the muscle fibers constitute 59% of the volume.
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PMID:Muscle fiber types in the cat middle ear muscles. II. Tensor tympani. 296 26

Rat pancreatic endocrine tumours were induced by administration of streptozotocin plus nicotinamide. Fifteen to eighteen months later tumours with wet weights of 0.1 to 224 mg were isolated. These tumours were compared with normal rat pancreatic islets. Insulin release from perifused tumours was stimulated by D-glucose, L-leucine, 2-ketoisocaproate, and D-glyceraldehyde, potentiated by theophylline and inhibited by norepinephrine. Compared with isolated rat pancreatic islets, however, insulin secretory responsiveness to glucose stimulation and insulin content were reduced in tumour tissue. Hypoglycaemia in tumour bearing rats and impaired diffusion of insulin out of the tumours may explain this difference. The pattern of enzyme activities observed in tumour tissue was typical for pancreatic endocrine tissue. The activities of succinate dehydrogenase, the two types of the monoamine oxidase, and alpha-glucosidase were in the normal range in tumour tissue. Only the activities of 5'nucleotidase and glutamate dehydrogenase were decreased. Immunocytochemical analysis of the tumours revealed that they contained an average of 91% B-cells. In addition 8% of D-cells were encountered. Proportions of A-cells and PP-cells ranged below 1%. Thus this endocrine tumour of the pancreas with a high proportion of functionally intact B-cells is an interesting model for studying regulation of secretion and endocrine tumour development.
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PMID:Secretory, enzymatic, and morphological characterization of rat pancreatic endocrine tumours induced by streptozotocin and nicotinamide. 299 5

The purpose of this study was to determine whether 8-12 wk of endurance training produces biochemical and histochemical adaptations in skeletal muscle in foxhounds. Analyses were performed on samples removed from gastrocnemius, triceps, and semitendinosus muscles of foxhounds before and after a treadmill running program. Biochemical analysis showed that training did not alter the activities of phosphofructokinase, beta-hydroxyacyl-CoA dehydrogenase, succinate dehydrogenase, or total phosphorylase. Histochemical analysis of myofibrillar actomyosin ATPase demonstrated three distinct classes of type II fibers and one type I fiber in the semitendinosus and triceps muscles and two type II and two type I fibers in the gastrocnemius muscle. Fiber type distribution and oxidative and glycolytic potentials, as indicated by nicotinamide adenine dinucleotide tetrazolium reductase or alpha-glycerophosphate dehydrogenase staining intensity, were unaltered by training. Similarly, capillary density, capillary-to-fiber ratios, and capillary area-to-fiber area ratios did not change with training. Thus, unlike humans and other mammals (i.e., rat), these foxhounds did not manifest biochemical or histochemical adaptations in skeletal muscle as the result of endurance training. This is consistent with the results of the study in which endurance training produced a 27% increase in maximal cardiac output and a 4% increase in maximal arteriovenous O2 extraction in foxhounds.
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PMID:Dynamic exercise training in foxhounds. II. Analysis of skeletal muscle. 316 58

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

Reduced nicotinamide adenine dinucleotide (NADH):ferricyanide reductase and DT-diaphorase specific activity in total homogenates of rat liver are markedly decreased as a very early biochemical event of hepatocarcinogenesis induced by the carcinogen 2-acetylaminofluorene (AAF). A 50 to 75% decrease in NADH:ferricyanide reductase was observed after 1 day of AAF (0.025% in the diet) feeding and persisted throughout a 7-week continuum of AAF administration. Carcinogen added directly to cell extracts had no effect. Similar results were obtained with single injections of either AAF or diethylnitrosamine. Xanthine dehydrogenase was also reduced in liver following AAF administration to nearly the same extent as NADH:ferricyanide reductase and DT-diaphorase. Total NADH-cytochrome c reductase and mitochondrial activity as estimated from succinic dehydrogenase were not affected by carcinogen administration relative to basal dietary controls. The reduced nicotinamide adenine dinucleotide phosphate:cytochrome c reductase that functions in drug detoxification was elevated. With livers of animals fed 4-acetamidophenol, a hepatotoxin chemically related to AAF, small decreases were noted in NADH:ferricyanide reductase, but not in xanthine dehydrogenase nor in DT-diaphorase. Initial lowering of these activities in the livers of the carcinogen-treated animals is preceded by or concomitant with a reduction in the levels of extramitochondrial pyridine nucleotides known from other studies to result from DNA damage.
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PMID:Decreased NADH-oxidoreductase activities as an early response in rat liver to the carcinogen 2-acetylaminofluorene. 396 29

By means of the light and electron microscopy, histochemical and cytophotometrical methods the anterior subarea of the cerebral limbic cortex has been studied in 30 experimental and 30 control rabbits. The experimental animals have been given 3, 15 and 30 sessions (1 h per day) of electric irritation (0.05 mA, 50 Hz, 1 msec) on the posterior hypothalamic field (PHF). Twelve rabbits from 30 control animals make an intact group and 18--a group with inactive electrodes inserted into the PHF. After 3 and especially after 15 sessions it has been revealed: in neurons--an acute swelling, edematous alterations, hyperchromatosis and shrinkage, changes in lactate dehydrogenase, succinic dehydrogenase, nicotinamide-adenine-dinucleotide-diaphorase and nicotinamide-adenine-dinucleotide-phosphate-diaphorase activities, in neuroglia--hypertrophy and weakly manifested hyperplasia. After 30 sessions synapses degenerated after the dark type are revealed. More intensive structural and metabolic changes are noted in the middle cytoarchitectonical complex. The changes of the enzymatic activity are considered as certain signs of weakening mitochondrial processes, connected with energy production, increasing glycolysis, decreasing level of the energetic provision of the cytoplasmic synthesis, arising under conditions of a disturbed transneuronal influence on the cortex by the hypothalamus.
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PMID:[Structural and metabolic changes in the limbic cortex of the rabbit in response to experimentation with the hypothalamus]. 408 71

A rapid method of preparing plasma membranes from isolated fat cells is described. After homogenization of the cells, various fractions were isolated by differential centrifugation and linear gradients. Ficoll gradients were preferred because total preparation time was under 3 hr. The density of the plasma membranes was 1.14 in sucrose. The plasma membrane fraction was virtually uncontaminated by nuclei but contained 10% of the mitochondrial succinic dehydrogenase activity and 25-30% of the RNA and reduced nicotinamide adenine dinucleotide cytochrome c reductase activity of the microsomal fraction. Part of the RNA and NADH-cytochrome c reductase activity was believed to be native to the plasma membrane or to the attached endoplasmic reticulum membranes demonstrated by electron microscopy. The adenyl cyclase activity of the plasma membrane fraction was five times that of Rodbell's "ghost" preparation and retained sensitivity to epinephrine. The plasma membrane ATPase activity was five times that of the homogenate and microsomal fractions. Electron microscopic evidence suggested contamination of the plasma membrane fraction by other subcellular components to be less than the biochemical data indicated.
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PMID:Preparation and characterization of a plasma membrane fraction from isolated fat cells. 424 33

Bacillus anthracis produces a toxin both in vitro and in vivo which, when injected intravenously into rats, brings about the death of the animals accompanied by gross pulmonary edema. Lung tissue removed prior to death showed, in vitro, a 30% reduction in overall oxidative metabolism (Q(o2)), whereas the nicotinamide adenine dinucleotide (NAD)-independent succinic dehydrogenase remained unaffected. The NAD concentration in the lungs of injected animals was reduced by 50%. Upon addition of NAD, the Q(o2) of lung tissue from injected animals rose to control values. At 45 min after toxin injection, the serum lactate concentration began to rise, showing about a 3.5-fold increase over controls after 75 min. No changes occurred in the pyruvate concentration. These changes may be explained by increased use of the pyruvate for glycolytic energy production with further loss of NAD. Additional experiments with liver, spleen, kidney, and brain tissues showed that the toxin-induced reduction of Q(o2) is an effect specific for lung tissue. Brain tissue showed a significant increase in oxidative metabolism upon the addition of the toxin, whereas the other tissues remained unaffected. It is suggested that a principal effect of the toxin is to inhibit, in lung tissue, the regeneration of NAD in the respiratory chain.
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PMID:Metabolic changes in nicotinamide adenine dinucleotide in response to anthrax toxin. 428 11


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