Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histochemical and ultrastructural properties of myoid cells in the thymus of the frog were investigated and compared with properties of skeletal muscle fibres. The histochemical reactions of phospholipids, phosphorylase, succinic dehydrogenase and adenosine triphosphatase activities in myoid cells were characterized by considerable variability. Individual myoid cells apparently possess different enzyme activities which correspond to different stages of development, maturity and degeneration of these cells. The mature mononucleated myoid cells have similar enzymatic properties to the fast muscle fibres of the frog. This finding has been extended by ultrastructural observations. Features, typical of fast muscle fibres of the frog, e.g. the presence of the M-line, straight and narrow Z-line and well developed triads were found in the majority of mature myoid cells.
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PMID:Histochemical and ultrastructural properties of myoid cells in the thymus of the frog. 15 83

The specific activities of the succinate dehydrogenase-coenzyme Q reductase were determined in mitochondria from the thymus and the spleen of aged mice (20, 22 and 24 months) as compared with young mice (10 weeks). Significant steep escalation of the deficiency of coenzyme Q-enzyme activity was observed in the thymus of all three groups of aged mice. No significant deficiency was found in the mitochondria of the spleen. The ratios between the liver weight:body weight and the spleen weight:body weight in young and aged mice are practically unchanged, but the thymus weight:body weight ratio decreases significantly in all three groups of aged mice. The described age-dependent anatomical and functional alterations in the thymus most likely form the base for the development of the T cell determined suppression of the immunological responsiveness, present in aged mice.
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PMID:Coenzyme Q deficiency in aged mice. 28 77

Chromomycin A3 is an antitumor antibiotic which blocks macromolecular synthesis via reversible interaction with DNA template only in the presence of divalent metal ions such as Mg2+. The role of Mg2+ in this antibiotic-DNA interaction is not well understood. We approached the problem in two steps via studies on the interaction of (i) chromomycin A3 and Mg2+ and (ii) chromomycin A3-Mg2+ complex(es) and DNA. Spectroscopic techniques such as absorption, fluorescence, and CD were employed for this purpose. The results could be summed up in two parts. Absorption, fluorescence, and CD spectra of the antibiotic change upon addition of Mg2+ due to complex formation between them. Analysis of the quantitative dependence of change in absorbance of chromomycin A3 (at 440 nm) upon input concentration of Mg2+ indicates formation of two types of complexes with different stoichiometries and formation constants. Trends in change of fluorescence and CD spectroscopic features of the antibiotic in the presence of Mg2+ at different concentrations further corroborate this result. The two complexes are referred to as complex I (with 1:1 stoichiometry in terms of chromomycin A3:Mg2+) and complex II (with 2:1 stoichiometry in terms of chromomycin A3:Mg2+), respectively, in future discussions. The interactions of these complexes with calf thymus DNA were examined to check whether they bind differently to the same DNA. Evaluation of binding parameters, intrinsic binding constants, and binding stoichiometry, by means of spectrophotometric and fluorescence titrations, shows that they are different. Distinctive spectroscopic features of complexes I and II, when they are bound to DNA, also support that they bind differently to the above DNA. Measurement of thermodynamic parameters characterizing their interactions with calf thymus DNA shows that complex I-DNA interaction is exothermic, in contrast to complex II-DNA interaction, which is endothermic. This feature implies a difference in the molecular nature of the interactions between the complexes and calf thymus DNA. These observations are novel and significant to understand the antitumor property of the antibiotic. They are also discussed to provide explanations for the earlier reports that in some cases appeared to be contradictory.
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PMID:Role of magnesium ion in the interaction between chromomycin A3 and DNA: binding of chromomycin A3-Mg2+ complexes with DNA. 155 Aug 24

A model of thymomegaly in puppies was used for a study of changes in the content of nucleic acids, protein, glycogen, ATP, cuprum, manganese, iron, zinc, succinate dehydrogenase and cytochromoxidase activity in tissues of the thymus, spleen, adrenal glands, liver and associated morphological changes in tissues of these organs, lymph nodes and the thyroid. In animals receiving sodium selenite normalization of the above indices was more marked than in untreated animals.
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PMID:[The biochemical and morphological changes in the body in experimental thymomegaly and their correction with sodium selenite]. 216 31

It has been established that the concentration of nucleic acids, protein, glycogen, ATP, copper, manganese, zinc as well as the activity of cytochromoxidase and succinate dehydrogenase in tissues of the thymus gland and spleen of albino rats a day after stimulation by phytohemagglutinin increase considerably reaching the maximal values three days later. Taking a prolonged term (up to 7 days) after phytohemagglutinin administration it is found that the content and activity of the studied indices in the thymus and spleen tissues lower regularly, but fail reaching normal values even 14 days after stimulation. In this case changes in the test indices in the spleen are less pronounced than in the thymus in all the studied periods. In the tissues of adrenals a tendency of changes in the manganese and copper content is like that in lymphoid organs in all periods after stimulation by phytohemagglutinin; other test indices have an opposite tendency.
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PMID:[Stimulation of energy plastic metabolism by phytohemagglutinin in lymphoid organs and adrenal glands]. 255 46

Young adult Wistar rats received 40 mg/kg of cyclosporin perorally for 21 days. Cyclosporin induced almost total disappearance of thymic medulla, whereas the cortex remained preserved. Although the density of cortical macrophages did not change significantly, their characteristics altered markedly and they became enlarged and rounded. In addition to an increase in acid phosphatase and nonspecific esterase activities, cortical macrophages developed very strong succinic dehydrogenase and chloroacetate esterase activities and a fine, granular, aldehyde fuchsin-positive cytoplasmic content. However, these cytoplasmic granules were PAS-negative and were not sudanophilic. Cortical macrophages retained their normal antigenic properties (which were studied by the use of ED1, ED2 and R-MC 41 monoclonal antibodies). Phagocytic cells in the remaining medullary islands retained their usual characteristics. The changes in cortical macrophages after cyclosporin treatment are discussed, especially in relation to the characteristics of macrophages of the cortico-medullary zone in the normal rat thymus.
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PMID:Macrophages of the rat thymus after cyclosporin treatment. Histochemical, enzymehistochemical and immunohistochemical study. 256 84

The cortex and medulla of the normal rat thymus are populated with scattered cells which are strongly positive for acid phosphatase and only weakly (cortex) or moderately (medulla) positive for nonspecific esterase. Corticomedullary zone is characterized, as a specific entity within the thymic tissue, by the presence of very large macrophages, highly positive for acid phosphatase and nonspecific esterase. Moreover, these cells, located exclusively in the corticomedullary zone, show very strong succinic dehydrogenase activity and contain the intracytoplasmic granules of varying size, which are aldehyde fuchsin, PAS, and oil red O positive. The presence of cholesterol was demonstrated within the lipid content.
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PMID:Enzyme-histochemical characterization of macrophages in the rat thymus, with special reference to metallophilic cells of the corticomedullary zone. 620 53

Dynamics of 5 marker enzymes activity from subcellular particles--succinate dehydrogenase, beta-glucosidase, arylsulphatases A and B, acid RNAase and glucose-6-phosphatase--were studied in liver, spleen, thymus and blood serum of rats after single intragastric administration of T-2 toxin at a dose of 3.8 mg/kg (LD50). The acute intoxication was accompanied by an early (within 1-3 hrs) and significant reduction of total proteins in the tissues studied. Distinct tissue- and organelle-tropic effects of T-2 toxin were found: the toxin induced a gradual decrease in activity of the enzymes studied in liver tissue, while selective activation of lysosomal hydrolases was observed in spleen and thymus tissues. The selective effect of T-2 toxin on spleen and thymus lysosomal hydrolases appear to be involved in the mechanism of action of the toxin.
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PMID:[Effect of T-2 toxin on the activity of organelle-specific enzymes of various rat organs]. 631 90

Subacute experiments were made to examine the effect of the grain contaminated with Fusarium sporotrichiella on the activity of organelle-specific enzymes of the liver, thymus, spleen, bone marrow and blood serum of rats (beta-N-acetylglucosaminidase, alpha-mannosidase, beta-galactosidase, arylsulfatases A and B, succinate dehydrogenase, glucose-6-phosphatase, alkaline phosphatase, ketoso-1-phosphate aldolase) and on the protein content. The feeding of the grain provoked an early appearance of the symptoms of intoxication and a change in the activity of organelle-specific enzymes manifesting in the activation of lysosomal hydrolases in the thymus, bone marrow and spleen and in a decrease in the blood serum activity of the most enzymes investigated.
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PMID:[Enzyme characteristics of food poisoning caused by grain contaminated with Fusarium sporotrichiella]. 642 31

The time-course of the ultrastructural changes and activities of 6 marker enzymes of subcellular particles (succinate dehydrogenase, beta-glucosidase, beta-N-acetylglucosaminidase, acid RNAse, glucose-6-phosphatase and 5'-nucleotidase) has been studied in the liver, spleen and thymus in rats administered T-2 toxin (mycotoxin produced by some Fusarium species). A pronounced difference in the effect of T-2 toxin on the organs has been found. In the liver, the toxin induced a destruction of rough endoplasmic reticulum membranes, reduced ribosome number and progressively decreased activities of most enzymes. In the spleen, early and significant ultrastructural disturbances of all the cell membrane components and simultaneous lysosomal activation were observed. The changes in the thymus were characterized by a fast development of cell hydratation, organelle swelling and necrosis of some thymocytes with parallel increase in repair processes, infiltration by phagocytes and a selective activation of lysosomal hydrolases in the end of experimental time (72 h.). The results obtained emphasize an importance of cellular and subcellular membrane alterations in the mechanism of T-2 toxin action.
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PMID:[Effect of T-2 toxin on organ ultrastructure and organelle-specific enzyme activity in rats]. 665 69


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