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)

The lead method for the histochemical demonstration of presumptive mitochondrial adenosinetriphosphatase was applied to biopsy and autopsy samples of the human vastus lateralis muscle. The effect of p-chloromercuribenzoate and of Triton X-100 was tested microdensitometrically and the activity of 'mitochondrial' ATPase was compared to the activity of enzymes of the oxidative metabolism succinic dehydrogenase and NAD-tetrazolium reductase. It is concluded that the ATPase activity displayed is not mainly mitochondrial. In autopsy material, it seems to be predominantly myofibrillar.
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PMID:The nonspecificity of the lead method for the histochemical demonstration of adenosine triphosphatases in human skeletal muscle fibres. 293 78

The effect of a single dose of 5 mg/kg body weight of aflatoxin B1 on rat liver mitochondrial enzymes, succinate dehydrogenase (SDH) and Mg++ adenosine triphosphatase (Mg++-ATPase) and on certain lipids were studies at various intervals of time from 3 to 24 hours. A significant decrease in the specific activity of SDH was observed after 6, 12, 18 and 24 hr treatment. The Mg++-ATPase activity remained unaffected up to 12 hr but appreciably decreased after, 18 and 24 hr of the treatment. The level of phospholipids and cholesterol were not altered after 3, 6 and 12 hr treatment, thereafter (18 and 24 hr) an increase was observed in both the lipids following the aflatoxin treatment. Medroxyprogesterone acetate (MPA) did not cause any alteration in the specific activities of these enzymes as well as levels of cholesterol and phospholipids. The treatment with MPA caused significant increase in contents of cytochromes P-450, b5 and activities of Arylhydrocarbon hydroxylase (AHH), UDP-glucuronyl transferase (UDP-GT) and NADPH-cytochrome C-reductase of hepatic microsomes. It was observed that pretreatment with medroxyprogesterone acetate (MPA) could significantly minimuze the depression caused in mitochondrial SDH and Mg++-ATPase activities by aflatoxin B1.
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PMID:Modification of aflatoxin B1-induced changes in certain mitochondrial enzymes and lipids by medroxyprogesterone acetate. 294 74

The effect of senescence on the metabolic profile of rat coronary arteries and arterioles was studied using enzyme histochemical techniques. In coronary arteries anaerobic metabolism predominates. In senescence an increase of adenosine triphosphatase (ATPase) occurred. The succinate dehydrogenase (SDH) and the respiratory chain metabolism marker NADH2-tetrazolium reductase (NADHD) showed an age-related decrease. Lactate dehydrogenase was unchanged. In the coronary arterioles, on the contrary, aerobic metabolism dominates. In senescence a significant decrease of NADHD and a moderate reduction of SDH and ATPase was observed. L-Carnitine administration significantly stimulated some enzymatic activities related to aerobic metabolism primarily at the arteriolar level.
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PMID:Metabolism of coronary vasculature in senescent rats--a histochemical study. 295 67

The morphology of the intestinal wall and the activity of certain mucosal enzyme systems in the course of neomycin treatment were evaluated. Conventional and, to study the role of the bacterial flora, germ-free rats received 500 mg neomycin daily by stomach tube. Rats were sacrificed after seven days and small intestine (proximal and distal part) together with segments of the colon were removed and prepared for histochemistry. The colon and proximal small intestine of untreated conventional and germ-free animals did not show appreciable differences in staining activity after treatment with neomycin. Neomycin diminished both in normal and germ-free rats the activity of NAD tetrazolium reductase, succinate dehydrogenase, esterase, alkaline phosphatase and acid phosphatase in the distal small intestine. The findings of this study indicate that explanations for the beneficial effects of neomycin on hyperammonemia in liver disease should not only include the bactericidal action of neomycin but also its influence on absorption and metabolic functions of the mucosal cells.
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PMID:Morphological effects of high dose neomycin sulphate on the small and large intestine. 296 22

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

A case of mitochondrial enzymopathy, called also ophthalmoplegia plus, was observed in a 31-year-old man. Histoenzymatic investigations demonstrated in the myocytes decreased and irregularity of reactions for succinic dehydrogenase, tetrazole reductase and mitochondrial ATPase. In electron microscopy paracrystalline structures, lamellar bodies and concentrically condensed cristae were seen in the mitochondria, and increased glycogen stores outside the mitochondria.
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PMID:[A case of mitochondrial enzymopathy]. 297 67

A simple procedure for preparation of highly purified soluble succinate-ubiquinone reductase from bovine heart mitochondrial particles is described. The enzyme exhibits four major bands on sodium dodecyl sulfate gel electrophoresis and contains (nmol per mg protein): covalently bound flavin, 6; non-heme iron, 53; acid-labile sulfur, 50; cytochrome b-560 heme, 1.2. The enzyme catalyzes thenoyltrifluoroacetone, or carboxin-sensitive (pure non-competitive with Q2) reduction of Q2 by succinate with a turnover number close to that in parent submitochondrial particles. The succinate reduced enzyme exhibits ferredoxin-type iron-sulfur center EPR-signal (g = 1.94 species) and a semiquinone signal (g = 2.00). An oxidized preparation shows a symmetric signal centered around g = 2.01. An unusual dissociation of the enzyme in the absence of a detergent is described. When added to the assay mixture from a concentrated protein-detergent solution, the enzyme does not reduce Q2 being highly reactive towards ferricyanide ('low Km ferricyanide reactive site'; Vinogradov, A.D., Gavrikova, E.V. and Goloveshkina, V.G. (1975) Biochem. Biophys. Res. Commun. 65, 1264-1269). The ubiquinone reductase, not the ferricyanide reductase was observed when the enzyme was added to the assay mixture from the diluted protein-detergent solutions. Thus the dissociation of succinate dehydrogenase from the complex occurs in the absence of a detergent dependent on the concentration of the protein-detergent complex in the stock preparation where the samples for the assay are taken from. An active antimycin-sensitive succinate-cytochrome c reductase was reconstituted by admixing of the soluble succinate-ubiquinone reductase and the cytochrome b-c1 complex, i.e., from the complexes which both contain the ubiquinone reactivity conferring protein (QPs). Cytochrome c reductase was also reconstituted from the succinate-ubiquinone reductase and succinate-cytochrome c reductase containing inactivated succinate dehydrogenase. The reconstitution experiments suggest that there exists a specific protein-protein (or lipid) interaction between QPs and a certain component(s) of the b-c1 complex.
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PMID:Studies on the succinate dehydrogenating system. Isolation and properties of the mitochondrial succinate-ubiquinone reductase. 299 19

The paper presents studies of the activity of lipid-dependent enzymes of the respiratory chain of the liver of rats exposed to increased ambient temperature. The animals were heated in a chamber under controlled humidity (45-55% relative humidity), with forcer air flow and regulated temperature of 21 degrees +/- 1 degree C (control group) and 28 degrees +/- 1 degree C or 35 degrees +/- 1 degree C. They were affected by a relevant temperature for 7 or 14 consecutive days, 6 hrs daily. The enzymes activities were determined in a fraction of submitochondrial particles. The studies demonstrated that under the increased ambient temperature (7 X 6 hrs), the activity of the respiratory enzymes is changed. A statistically significant increase in the activity of NADH dehydrogenase, NADH cytochrome c reductase and cytochrome oxidase was found along with a decrease in the activity of succinate cytochrome c reductase and succinate dehydrogenase. On prolongation of thermal exposure (14 X 6 hrs) the activity of succinate dehydrogenase and succinate reductase: cytochrome c was further decreased. The activities of the other test enzymes did not exhibit any statistically significant differences as compared to controls. Kinetic tests of succinate dehydrogenase point to conformational changes of the enzyme when affected by an increased ambient temperature. This confirms the important role of this enzyme in the animals adaptation to thermally varying environmental conditions.
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PMID:Influence of repeated exposure to elevated environmental temperature on the activity of respiratory enzymes of rat liver mitochondria. 302 93

QP-S, a ubiquinone (Q) protein, accepts electrons from succinate through succinate dehydrogenase (SDH). A new method has produced a preparation of QP-S which has a different amino acid composition and SDS gel electrophoretic pattern from that of the old preparation (Biochemistry 19, 3579-3585 (1980)). The new preparation contains less than 1 nmol heme/mg protein; the activity of the preparation was not proportional to its heme content. A thenoyltrifluoroacetone sensitive free radical signal was detected by EPR spectroscopy in succinate-Q reductase reconstituted from this QP-S and SDH; the characteristics of this species identify it as ubisemiquinone. At pH 7.4, the Em of the two electron step was about 70 mV with E1 = 5 mV and E2 = 125 mV. The properties of the radical differed slightly from those of "Qs" radical in more intact preparations (e.g. submitochondrial particles). The present is the simplest system in which such a succinate reducible ubisemiquinone free radical has been demonstrated.
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PMID:Stabilized ubisemiquinone in reconstituted succinate ubiquinone reductase. 303 47

Exposure of rats to elevated temperature of 28 degrees C or 35 degrees C for 3 days six hours daily resulted in a decreased rate of oxidation with succinate or glutamate + malate as substrates, by the mitochondria of liver. The higher decrease was observed in environment temperature of 35 degrees C. There was no change in ADP/O ratio. The activities of NADH: cytochrome c reductase and cytochrome oxidase were stimulated but activities of succinate dehydrogenase and succinate cytochrome reductase were decreased.
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PMID:Influence of increased environmental temperature on oxidation processes in rat liver mitochondria. 303 73


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