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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)
Effects of changes in dietary protein have been investigated on three mitochondrial enzymes,
succinate dehydrogenase
,
isocitrate dehydrogenase
and cytochrome oxidase. Weanling rats (21 days old) were fed for 30 days on (a) a commercially produced diet (CPD) containing 21.0% dietary protein and (b) a low protein-high carbohydrate diet (LPD) containing 3.47% dietary protein. Signs of protein-energy malnutrition developed in the animals having the low protein diet. The mitochondrial enzymes were assayed. Some of the experimental rats were repleted by feeding them on a protein-rich diet for 3 weeks, and the same mitochondrial enzymes were assayed. The activity of mitochondrial cytochrome oxidase, which fell to 24% of the control values during the period of deficiency, rose to 91% of the values for control rats during rehabilitation. The activities of
succinate dehydrogenase
and NAD+-isocitrate dehydrogenase fell to 75 and 73% of the control values, respectively, during depletion and rose to 83 and 88% during repletion in line with the general rate of recovery of the malnourished rats as reflected by the changes in the body weights during repletion. These results show that mitochondrial cytochrome oxidase is very sensitive to changes in dietary protein. Its activity drops sharply with reduction in dietary protein intake and rises rapidly, outstripping the rate of general recovery on reverting to a protein-rich diet.
...
PMID:Cytochrome oxidase status in protein-energy-deficient rats. 300 81
It has been reported that the mitochondrial cytochromes and citrate cycle enzymes occur in constant proportions to each other and increase or decrease roughly in parallel in response to various stimuli. The purpose of this study was to determine whether this proportionality is an obligatory consequence of the way in which mitochondria are assembled. Severe iron deficiency was used to bring about decreases of the iron-containing constituents of the mitochondrial respiratory chain in skeletal muscle. Cytochrome c concentration and cytochrome oxidase activity were decreased approximately 50%, while
succinate dehydrogenase
and NADH dehydrogenase activities were decreased by 78% in iron-deficient muscle. On electron microscopic examination, mitochondria in iron-deficient muscles had relatively sparse numbers of cristae. The iron deficiency had little or no effect on the levels of a range of mitochondrial matrix enzymes, including citrate synthase,
isocitrate dehydrogenase
, fumarase, aspartate aminotransferase, 3-hydroxyacyl-CoA dehydrogenase, 3-ketoacid-CoA transferase, and acetoacetyl-CoA thiolase. These results show that the usual constant proportions between the constituents of the mitochondrial respiratory chain and matrix enzymes are not obligatory; they provide evidence that mitochondrial matrix enzymes and respiratory chain constituents can be incorporated into mitochondria independently and that the ratios between them can vary within wide limits.
...
PMID:Perturbation of mitochondrial composition in muscle by iron deficiency. Implications regarding regulation of mitochondrial assembly. 302 53
Acute cooling of rats led to stimulation of NAD+-dependent
isocitrate dehydrogenase
(ICDH),
succinate dehydrogenase
(
SDH
) and NAD(P)+-transhydrogenase (TH) but did not affect the
NADP+-ICDH
activity in liver, heart and skeletal muscle mitochondria. After pretreatment of the animals with propranolol the stimulating effect was decreased, thus suggesting that endogenous catecholamines and beta-adrenoreceptors are of importance in activation of NAD+-ICDH,
SDH
and TH. The effects of cooling, noradrenaline and cAMP did not summarize. Role of catecholamines in stimulation of mitochondrial oxidative enzymes under conditions of cooling is discussed.
...
PMID:[Stimulation of mitochondrial oxidative enzymes in acute cooling and its catecholamine mechanisms]. 302 85
The damaging effects of ADP/Fe/NADPH-induced lipid peroxidation were studied on the enzymes and membranes of rat liver mitochondria. Succinate, an inhibitor of mitochondrial lipid peroxidation, prevented or delayed most of the damage caused by the peroxidation on different mitochondrial structures and functions. There were marked abnormalities on the electrophoretic pattern of mitochondrial proteins during the course of lipid peroxidation. The disappearance of particular polypeptide bands and the accumulation of high-molecular-weight aggregates could be observed. Succinate was found to delay these effects. As a consequence of lipid peroxidation the succinate oxidase activity of mitochondria was decreased. The
succinate dehydrogenase
enzyme and the component(s) of the respiratory chain were inactivated. Succinate prevented the inactivation of
succinate dehydrogenase
but did not protect the other components of terminal oxidation chain. From the matrix enzymes the glutamate dehydrogenase retained its full activity but the
NADP-linked isocitrate dehydrogenase
was inactivated. The mitochondrial membranes became permeable to large protein molecules. Succinate prevented the inactivation of
isocitrate dehydrogenase
and delayed the release of protein molecules from mitochondria.
...
PMID:Effect of succinate on mitochondrial lipid peroxidation. 2. The protective effect of succinate against functional and structural changes induced by lipid peroxidation. 303 29
With an aim to investigate the relative sensitivity of various renal structures to allograft rejection, we analyzed the histochemical reaction intensity of seven enzymes prominently displayed in various rat kidney components, and correlated the expression of these enzymes both to the degree of intra-graft inflammation and to the expression of class II MHC antigens in graft capillary endothelial cells. Syngeneic transplants and normal renal tissue were used as controls. At the peak of inflammation, on the fifth day after transplantation, adenosine triphosphatase activity of vascular endothelial cells was strongly reduced in the peritubular capillary endothelium of the allograft, moderately in the glomerular endothelium but very little in the endothelium of arteries and veins. Lactate dehydrogenase,
succinate dehydrogenase
,
isocitrate dehydrogenase
, alkaline phosphatase, acid phosphatase and glucose-6-phosphatase activities were moderately reduced in the proximal tubular cells of the allograft and even less in the distal tubular cells. The results suggest that the prime target of the host immune attack is the intertubular capillary endothelium, whereas the distal tubular cells are relatively insensitive to immune injury.
...
PMID:Renal target structures in acute allograft rejection: a histochemical study. 303 33
Ten hours after the 5-day space flight on Cosmos-1514 rats were examined for oxidative phosphorylation in mitochondria isolated from the posterior femoral muscles as well as for Krebs cycle enzymes and glycolysis in the mitochondrial and cytoplasmic fractions of the muscles. The mitochondrial respiration rate in various metabolic states was similar in flight rats and vivarium controls. After flight calculated parameters of energy efficacy of respiration as well as activity of malate dehydrogenase,
isocitrate dehydrogenase
and total lactate dehydrogenase remained unchanged. Unlike the flight rats, the synchronous controls showed signs of the stress-reaction: uncoupling of oxidative phosphorylation and oxalacetate inhibition of
succinate dehydrogenase
. Comparison of these findings with those from prolonged space flights indicates that inhibition of oxidative metabolism and glycolysis in mixed muscles which was demonstrated in the 20-day space flight does not develop immediately after launch but occurs within the time interval between mission days 6 and 18.
...
PMID:[Energy reactions in the skeletal muscles of rats after short-term space flight on Kosmos-1514]. 304 95
The activities of the mitochondrial enzymes citrate synthase (citrate oxaloacetatelyase, EC 4.1.3.7),
NADP-linked isocitrate dehydrogenase
(threo-Ds-isocitrate:NADP+ oxidoreductase (decarboxylating),
EC 1.1.1.42
), and
succinate dehydrogenase
(succinate: FAD oxidoreductase, EC 1.3.99.1) as well as their kinetic behavior in the two developmental forms of Trypanosoma cruzi at insect vector stage, epimastigotes and infective metacyclic trypomastigotes, were studied. The results presented in this work clearly demonstrate a higher mitochondrial metabolism in the metacyclic forms as is shown by the extraordinary enhanced activities of metacyclic citrate synthase,
isocitrate dehydrogenase
, and
succinate dehydrogenase
. In epimastigotes, the specific activities of citrate synthase at variable concentrations of oxalacetate and acetyl-CoA were 24.6 and 26.6 mU/mg of protein, respectively, and the Michaelis constants were 7.88 and 6.84 microM for both substrates. The metacyclic enzyme exhibited the following kinetic parameters: a specific activity of 228.4 mU/mg and Km of 3.18 microM for oxalacetate and 248.5 mU/mg and 2.75 microM, respectively, for acetyl-CoA.
NADP-linked isocitrate dehydrogenase
specific activities for epimastigotes and metacyclics were 110.2 and 210.3 mU/mg, whereas the apparent Km's were 47.9 and 12.5 microM, respectively. No activity for the NAD-dependent isozyme was found in any form of T. cruzi differentiation. The particulated
succinate dehydrogenase
showed specific activities of 8.2 and 39.1 mU/mg for epimastigotes and metacyclic trypomastigotes, respectively, although no significant changes in the Km (0.46 and 0.48 mM) were found. The cellular role and the molecular mechanism that probably take place during this significant shift in the mitochondrial metabolism during the T. cruzi differentiation have been discussed.
...
PMID:Differential energetic metabolism during Trypanosoma cruzi differentiation. I. Citrate synthase, NADP-isocitrate dehydrogenase, and succinate dehydrogenase. 305 38
The present study was conducted on bone tissue responses to irradiation towards a treatment model of mandibular irradiation injury by comparing the results of experimental observations of irradiation effects on rabbit hind legs and rat mandibular bones (paper I, II and III) with clinical observations of irradiation effects on the human mandible (paper IV, V and VI). The main results of the study were as follows: Bone marrow haemorrhage, eosinophilia and incipient edema were encountered in the rabbit leg one day after a single irradiation dose. Edema and fibrosis were the salient features after five weeks, while both regenerative and fibrotic changes predominated eleven weeks after irradiation. The changes were the more extensive the greater the irradiation dose was. Empty lacunae as a sign of cell damage in cortical bone already appeared on the first day after irradiation; this effect reached its maximum when the dose was 20 Gy or more. Bone marrow and subcutaneous tissue pO2 and pCO2 were measured by means of implanted Silastic tonometers in irradiated and nonirradiated rabbit hind legs. Single dose irradiation was followed by a rapid, dose dependent decrease of marrow pO2. The corresponding effect on pCO2 was weaker and appeared later. The response to hyperoxia in the bone marrow became weaker when the irradiation dose increased. Less significant was the response of CO2 tension to hyperoxia. O2 and CO2 tensions were recovered after single dose irradiation both in subcutaneous tissue and in bone marrow, but the reduction was less in bone marrow. During the twelve weeks observation period clearly better recovery in tissue gas tensions was observed in subcutaneous tissue than in bone marrow. Nonirradiated periosteal grafts on irradiated bone cavities in the rabbit tibia induced more rapid and intense mature bone formation than irradiated periosteal grafts. The irradiated periosteum, even after a single dose of 20 Gy, had some osteogenetic capacity. The alkaline phosphatase content was lowered eight weeks after surgery in irradiated legs but clearly exceeded control values twelve weeks after surgery indicating new bone formation. Lysosomal enzyme DAP II contents were increased in all irradiated specimens as a sign of disturbed bone formation. The tissue concentrations of acid phosphatase, cytochrome oxidase, lactate dehydrogenase,
isocitrate dehydrogenase
, glucose-6-phosphate dehydrogenase and
succinate dehydrogenase
in the immediate postirradiation period showed a greater increase in activity in the cut lines of the irradiated rat mandibles than in those of the nonirradiated mandibles.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Bone tissue response to irradiation and treatment model of mandibular irradiation injury. An experimental and clinical study. 309 Aug 54
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.
...
PMID:[Enzyme histochemistry of the pig placenta. III. Histotopics of enzymes in the uterine epithelium]. 309 49
The metabolic pathways of glucose were studied by histochemical reactions in some species of gastropods living in different habitats. The glycolytic pathway is histochemically indicated by positive results for glucose-6-phosphate isomerase, fructose-1,6-biphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, and D-lactate dehydrogenase. The enzymes of the Krebs cycle gave different responses:
isocitrate dehydrogenase
and L-malate dehydrogenase were positive, whilst
succinate dehydrogenase
was constantly negative. Malate synthetase activity was also demonstrated. Despite L-glutamate dehydrogenase is undetectable, the presence of transaminase indicates the gluconeogenetic route. Phosphoglucomutase and glucose-6-phosphate phosphatase appear also positive. The metabolic meaning of our results were discussed.
...
PMID:Histochemical research on metabolic pathways of glucose in some species of Mollusca Gastropoda. 311 Nov 50
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