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)

X-band electron-paramagnetic-resonance spectroscopy at 4.2--77K combined with measurements of oxidation-reduction potential was used to identify iron--sulphur centres in Arum maculatum (cuckoo-pint) mitochondria. In the oxidized state a signal with a derivative maximum at g = 2.02 was assigned to succinate dehydrogenase centre S-3. Unreduced particles showed additional signals at g = 2.04 and 1.98 (at 9.2 GHz), which may be due to a spin-spin interaction. In the reduced state a prominent signal at g = 1.93 and 2.02 was resolved into at least three components that could be assigned to centres S-1 and S-2 of succinate dehydrogenase (midpoint potentials -7 and -240 mV respectively at pH 7.2) and a small amount of centre N-1b (e'o= -240 mV) of NADH-ubiquinone reductase. In addition, changes in line shape around -10 mV indicated the presence of a fourth component in this signal. The latter was more readily reduced by NADH than by succinate, suggesting that it might be associated with the external NADH dehydrogenase. The iron-sulphur centres of NADH-ubiquinone reductase were present in an unusually low concentration, indicating that the alternative, non-phosphorylating, NADH dehydrogenase containing a low number of iron-sulphur centres may be responsible for most of the high rate of oxidation of NADH.
Biochem J 1977 Sep 15
PMID:Iron-sulphur centres in mitochondria from Arum maculatum spadix with very high rates of cyanide-resistant respiration. 59 30

In salt-depleted and salt-loaded rat kidneys a study was made of the structural segmentation of the proximal convoluted tubule (PCT) and the histochemical activity of non-specific acid and alkaline phosphatases and succinate dehydrogenase in the same segments. No quantitative structural or segmental alterations were observed, but significant changes in enzyme activity occured. These comprised: 1) A decrease in activity of acid phosphatase in segment 1 and the transitional zone in salt-depleted kidneys, and an increase in enzyme activity in segment 2 in salt-loaded kidneys. 2) a decrease in alkaline phosphatase activity in segment 2 in both salt-depleted and salt-loaded kidneys and 3) a decrease in succinate dehydrogenase activity in segment 2 in salt-depleted kidneys, and an increase in activity in the same segment in salt-loaded kidneys. Thus long-term variation in sodium intake are followed by segment-correlated variations in the activity of acid and alkaline phosphatase and succinate dehydrogenase in the PCT.
Acta Pathol Microbiol Scand A 1978 Sep
PMID:Histochemical enzyme activity correlated to the structural segmentation of the proximal convoluted tubule in salt-depleted and salt-loaded rat kidneys. 71 4

An investigation of succinate dehydrogenase activity in the wall of rabbit aorta was carried out. The level of succinate dehydrogenase per se in the smooth muscle cells was found to be fairly high, while the mitochondrial level of carrier CoQ was low. The latter may explain the low level or lack of activity of succinate dehydrogenase in these cells as noticed by previous authors. A reliable image of the actual level of succinate dehydrogenase was obtained only by adding CoQ10 to the incubation system. PMS should be avoided, as it induced a "Nothing dehydrogenase" reaction even at low concentrations.
Histochemistry 1978 Sep 28
PMID:Succinate dehydrogenase activity in the wall of rabbit aorta. The histochemical use of PMS and exogenous coenzyme Q10 as intermediate carriers. 72 31

1. Enzyme activities (units/g wet wt.) were determined in the caput and cauda epididymidis and in epididymal spermatozoa of the rat. 2. The activity of most enzymes in the cauda was between 50 and 100% of that in the caput, except that ATP citrate lyase was barely detectable in the cauda. 3. Spermatozoa, unlike epididymal tissue, contained sorbitol dehydrogenase but lacked ATP citrate lyase. NADP+-malate dehydrogenase, mitochondrial glycerol 3-phosphate dehydrogenase, succinate dehydrogenase, carnitine acetyltransferase and citrate synthase were 5 to 400 times as active in spermatozoa as in epididymal tissue. 4. 2-Oxoglutarate dehydrogenase was the least active member of the tricarboxylic acid cycle in all tissues and most closely matched the measured flux through the cycle. 5. The concentrations of hydroxyacyl-CoA dehydrogenase and carnitine palmitoyltransferase were equivalent to the more active enzymes of the tricarboxylic acid cycle, indicating the capacity for extensive lipid oxidation, and the presence of 3-hydroxybutyrate dehydrogenase suggests that these tissues can also oxidize ketone bodies. 6. Transfer of reducing equivalents from cytoplasm to mitochondrion is unlikely to occur by means of the glycerol phosphate cycle because mitochondrial glycerol 3-phosphate dehydrogenase is relatively inactive in epididymal tissue, whereas the cytoplasmic enzyme has little activity in spermatozoa, but transfer may be accomplished by the malate-aspartate shuttle. 7. Transfer of acetyl units from mitochondrion to cytoplasm could be effected by the pyruvate-malate cycle in the caput of androgen-maintained rats, but not in the other tissues because of the low activity of ATP citrate lyase. Acetyl unit transfer could take place via acetylcarnitine, mediated by carnitine acetyltransferase. 8. Castration resulted in a decrease in the concentration of nearly all enzymes, although subsequent administration of testosterone restored concentrations to values similar to those in animals maintained by endogenous androgen. The extent to which enzyme concentration was changed by an alteration in androgen status was highly variable, but was most marked in the case of pyruvate carboxylase.
Biochem J 1978 Sep 15
PMID:Activity and androgenic control of enzymes associated with the tricarboxylic acid cycle, lipid oxidation and mitochondrial shuttles in the epididymis and epididymal spermatozoa of the rat. 72 83

Cations were generally ineffective in stimulating succinate transport in a succinate dehydrogenase mutant of Bacillus subtilis unless accompanied by polyvalent anions; phosphate and sulfate being particularly active. The Km values for the phosphate or sulfate requirement were approx. 3 mM. Biphasic kinetics were characteristic of both the succinate (Km values 0.1 and 1 mM), and inorganic phosphate (Km values 0.1 and 3 mM) transport system(s). The phosphate transport system(s) was repressed by high inorganic phosphate and a coordinate increase in the transport of phosphate, arsenate, and phosphate-stimulated succinate transport accompanied growth in low phosphate media. A class of arsenate resistant mutants were simultaneously defective in the transport of arsenate, phosphate and succinate when cells were repressed for phosphate transport, however, the transport of these ions was regained in these mutants when grown in low phosphate media. Organic phosphate esters did not stimulate succinate transport in arsenate resistant mutants but were effective after growth in low phosphate media. Growth under phosphate limitation permitted the simultaneous regain of both phosphate and sulfate dependent succinate transport activities whereas sulfate limitation alone was ineffective. Succinate was not transported by an anion exchange diffusion mechanism since phosphate efflux was low or absent during succinate transport. The transport of C4-dicarboxylates in B. subtilis is strongly stimulated by intracellular polyvalent anions. The absence of an anion permeability mechanism precludes succinate transport but partial escape from this restriction is mediated by the derepression of a phosphate transport system.
Biochim Biophys Acta 1975 Sep 02
PMID:Succinate transport in Bacillus subtilis. Dependence on inorganic anions. 81 Jan 62

1. Six subjects were trained using a one-leg bicycle exercise for 2 months. The untrained leg served as control. After the training period, muscle oxidative capacity, determined as succinate dehydrogenase activity, was 27% higher in the trained (as opposed to the control) leg (P < 0.05).2. When the subjects in this situation performed a 1 h two-legged submaximal bicycle exercise bout (150-225 W), determinations of V(O2) of the single leg (leg blood flow x (A-V)(O2) difference) revealed that they appeared to choose to work harder with their trained than with their untrained leg, so as to make the relative loads for the two legs the same.3. Determinations of O(2) and CO(2) on femoral arterial and venous blood demonstrated that the R.Q. was lower in the trained as compared to the untrained leg, 0.91 cf. 0.96 (10 min) and 0.91 cf. 0.94 (50 min) (P < 0.05).4. That metabolism of fat was more pronounced in the trained leg was further supported by the finding of a significant net uptake of free fatty acids in this leg only. Moreover, a lower release of lactate from the trained leg was demonstrated.5. It is suggested that the shift towards a more pronounced metabolism of fat in the trained leg is a function of an increased muscle oxidative capacity.
J Physiol 1977 Sep
PMID:Training induced adaptation of skeletal muscle and metabolism during submaximal exercise. 90 9

Expression of the damaging effect of adrenalin on the myocardium of rats adapted to hypoxia was studied under condition of adrenalin being injected into the integral body or in perfusion of an isolated heart. The damage was tested by the histoenzymatic reaction for the succinic dehydrogenase activity and staining for lipids. When the cardiotoxic dose (2.0 mg/kg) of adrenalin was injected intramuscularly to the adapted rats no damage of the myocardium was found, but perfusion of the isolated heart with adrenalin (20 microgram/ml) induced cardiocyte micronecrosis. The volume of these necroses was statistically less than in the isolated heart of the intact rats under analogous treatment. The difference between the sensitivity of the myocardium in vivo and in vitro indicated that in rats adapted to hypoxia the phenomenon of the myocardium protection from the damaging effect of adrenalin acted on the integral body level. An increased resistance of the myocardium proper seems to be caused by the increase of the metabolic system force during adaptation.
Biull Eksp Biol Med 1977 Sep
PMID:[Myocardial resistance to adrenaline in rats adapted to hypoxia]. 91 73

The indices of central hemodynamics and myocardial contractility were studied by poly- and mechanocardiography in 25 patients with stage I-IIA circulatory insufficiency prior to and after treatment with 1-dioxyphenlalanine. The content of lactic and pyruvic acids in the blood and erythrocyte permeability to 32P were determined at the same time. The activity of the redox enzymes was studied in rats with experimentally induced circulatory insufficiency on the background of 1-DOPA medication. It was established that contractility of the heart and indices of central hemodynamics improved due to the effect of 1-DOPA. A decrease in the lactate concentration and an elevation of the pyruvate level in the blood of patients were noted. In animal experiments increased activity of cytochrome oxidase, succinic dehydrogenase, and alkaline and acid phosphatase in the myocardium was demonstrated.
Kardiologiia 1977 Sep
PMID:[Clinico-experimental evaluation of therapeutic effectiveness of 1-dihydroxyphenylalanine in circulatory insufficiency]. 92 3

Mitochondrial abnormalities are reported in four cases of phaeochromocytoma. These abnormalities include swelling and scant cristae, intramitochondrial dense bodies, septate-like junctions, intercristal fusion plus spheroidal bodies, and intramitochondrial rodlets. These structural mitochondrial changes are associated with reduction in activity of the mitochondrial enzymes, monoamine oxidase and succinic dehydrogenase.
Cell Tissue Res 1976 Sep 14
PMID:Mitochondrial abnormalities in human phaeochromocytoma. 99 Dec 14

Eight patients under routine care for periodontitis received oral treatment with a form of coenzyme Q (7 / CoQ10 and 1 / hexahydrocoenzyme Q4). An unchanged plaque score showed the patients cooperated and were under plaque control. The periodontal score decreased (p less than 0.01) on CoQ treatment. Unexpectedly, the periodontal pocket depth decreased (P less than 0.05) on CoQ treatment since all patients were considered candidates for surgical intervention. Healing was so excellent 5-7 days post-biopsy that the biopsy sites were difficult to locate. The healing was viewed as extraordinarily effective. The mean value of the specific activities of the succinate dehydrogenase-coenzyme Q10 reductase of gingival biopsies increased (P less than 0.05) during treatment which could correlate with the extraordinarily healing. Treatment of periodontitis with coenzyme Q should be considered as adjunctive treatment with current dental practice.
Res Commun Chem Pathol Pharmacol 1975 Sep
PMID:Bioenergetics in clinical medicine. II. Adjunctive treatment with coenzyme Q in periodontal therapy. 110 47


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