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)

Aging-dependent changes of some enzymatic activities related to the glycolytic anaerobic pathway (lactate-dehydrogenase, LDH), to the Krebs's cycle (succinate dehydrogenase, SDH) and to the activity of the respiratory oxidative chain (NADH2 - tetrazolium reductase, NADH-D) were studied in the nephron of 4-(young) and 24- (aged) month-old female Wistar rats. In the renal glomeruli LDH and NADH-D activities were reduced with aging, while SDH did not undergo aging-dependent changes. In both the proximal and the distal convoluted tubules, LDH reactivity slightly increased while NADH-D remarkably decreased in old rats; SDH did not show aging-dependent changes. In the loop of Henle LDH was slightly increased, SDH was unchanged and NADH-D was decreased in aged in comparison to young rats. The three enzyme activities investigated were significantly reduced in the collecting tubules of aged animals. The above results are suggestive of the existence of aging changes in mechanisms related with energy transduction in the rat kidney, affecting at a different extent the cell populations of the nephron.
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PMID:Enzyme histochemistry of aging rat kidney. 182 23

The relationships between ultrastructural and metabolic profiles in different types of single muscle fiber after hindlimb suspension in rats were examined. Glycolytic (lactate dehydrogenase, LDH; phosphofructokinase, PFK) and oxidative (succinate dehydrogenase, SDH; malate dehydrogenase, MDH) enzyme activities in extensor digitorum longus (EDL) and soleus (SOL) muscles were measured. Relative mitochondrial and lipid droplet volumes were also measured in single muscle fiber of different types. Glycolytic enzyme activity in EDL muscle and oxidative enzyme activity in soleus muscle decreased following suspension for 2 weeks. LDH and PFK activities in fast-twitch (FG, fast-twitch glycolytic; FOG, fast-twitch oxidative glycolytic) fibers and oxidative enzymes in FOG and FG fibers decreased following suspension. Relative mitochondrial volume decreased significantly in all types (SO, slow-twitch oxidative; FOG, and FG) of fibers following suspension. The mitochondrial volume in SO fiber of the control group was significantly (p less than 0.01) higher than that of suspended group; however, SDH and MDH activities were not different between the control and suspended groups. The structural and metabolic changes following hindlimb suspension were influenced by different factors, respectively. Changes in ultrastructural and metabolic profiles in response to the hindlimb suspension differed according to the type of fibers.
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PMID:Ultrastructural and metabolic profiles on single muscle fibers of different types after hindlimb suspension in rats. 252 86

We studied the testis of Wistar rats weighing 280-300 gms. following the administration of a single, acute intracardiac dose of methionine-enkephalin (100 microliters of 50% met-enkephalin solution), or a chronic intramuscular dose (50 microliters of 40% met-enkephalin solution). Rats were sacrificed at 15, 30 and 60 minutes following acute injection. Those on chronic treatment were injected once daily for 10 or 20 days. For the study, we utilized 105 male Wistar rats; 30 comprised the control group, and 75 comprised the study group. The following staining methods were used: 1) succinate dehydrogenase, 2) lactate dehydrogenase, 3) ATPase, 4) acid phosphatase, 5) alkaline phosphatase. We observed marked histoenzymological changes in the rat testis. Particularly noteworthy was a marked change in the energy pathways consisting of a decreased activity of aerobic pathways (decreased SDH activity), increased anaerobic activity (increased LDH activity), and consequently, decreased cellular energy stores (decreased ATPase activity). Similarly, changes were observed in other nonspecific enzymes that led to a fall in acid phosphatase activity and a rise in alkaline phosphatase activity.
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PMID:[Effects of met-enkephalin on the testis. III. Histoenzymatic study]. 253 59

The different distribution of cytochemically demonstrable enzymes: lactate dehydrogenase (LDH, 1.1.1.27), succinate dehydrogenase (SDH, 1.3.99.1), dihydrofolate reductase (DHFR, 1.5.1.3), acid phosphatase (AcP, 3.1.3.2) and alkaline phosphatase (ALP, 3.1.3.1), has been documented in Yoshida ascites hepatoma cells in vivo or stored at 80 degrees C. The dehydrogenase activities (LDH, SDH, DHFR) show a strong reaction in all samples. An increased level of these enzyme activities has been observed in the malignant cells spreading through the organs of tumor bearing rats. On the contrary, in the same samples, acid and alkaline phosphatase activities are very low. The strong dehydrogenase activities observed in Yoshida ascite cells stress the rapid turnover of tumor cells. Our results indicate that the histochemical method may be a useful tool to detect the scattered tumor cells. Furthermore, the cytochemical methods allow the characterization of the metabolic pathways employed by the primary and disseminated tumor cells.
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PMID:[Cytochemical study of cells of primary and disseminated ascite Yoshida tumor cells]. 276 51

Changes in carbohydrate metabolism were studied in midgut gland, muscle, and gill tissues of marine prawn Penaeus indicus exposed to a sublethal concentration (0.3 ppm) of phosphamidon. A significant decrease in glycogen and pyruvate and an increase in lactate content were observed in all phosphamidon-exposed prawn tissues after 96 hr. An increase in phosphorylase a and aldolase activity levels suggested the increased formation of triose sugars during phosphamidon toxicity. LDH activity was considerably decreased and an increment in lactate content was observed which indicates reduced mobilization of pyruvate into the citric acid cycle. Glucose-6-phosphate dehydrogenase activity was considerably increased, suggesting the enhanced oxidation of glucose in the hexose monophosphate shunt pathway. Krebs cycle enzymes such as NAD-isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase were found to be decreased, suggesting the impairment in mitochondrial oxidative metabolism due to the acute toxic impact of phosphamidon. Cytochrome-c oxidase and Mg2+ ATPase activity levels were also decreased considerably, suggesting impaired energy synthesis and breakdown during phosphamidon toxicity, as a result of reduced oxidation of glucose aerobically. The increase in acid and alkaline phosphatase activities indicates the enhanced breakdown of phosphate to release energy in view of inhibiton or impairment in the ATPase system during phosphamidon-induced stress. These results suggest that phosphamidon has a profound effect on the oxidative metabolism of prawn which results in the triggering of compensatory metabolic pathways for survivability.
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PMID:Modulation of carbohydrate metabolism in the selected tissues of marine prawn, Penaeus indicus (H. Milne Edwards), under phosphamidon-induced stress. 337 38

The behavior of cytoplasmic and mitochondrial enzymes has been studied in rat liver at 1, 5, and 24 hr after 60 min of ischemia using histochemical methods. This period of ischemia resulted 24 h after ischemia in liver cell necrosis in about 15% of the volume of the ischemic liver lobes. As early as after 1 hr reperfusion lactate dehydrogenase (LDH, cytoplasm) activity decreased in a certain proportion of the liver parenchymal cells, whereas glutamate dehydrogenase (GDH, mitochondrial matrix) activity started to decrease after 5 hr reperfusion; the activities of mitochondrial membrane enzymes, monoamine oxidase and succinate dehydrogenase, did not decrease before 24 hr of reperfusion. It has been concluded that the early decrease in LDH activity is caused by leakage into the blood and reflects reversible damage; when this decrease is accompanied by a decrease in GDH activity irreversible liver cell damage is assumed. Diminished activity of mitochondrial membrane enzymes, due to leakage and denaturation, is observed when real necrosis can be assessed.
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PMID:Changes in cytoplasmic and mitochondrial enzymes in rat liver after ischemia followed by reperfusion. 367 63

The influence of low frequency (8-10 Hz) electrical stimulation on denervated fast-twitch muscle from rabbit was investigated. Prolonged direct stimulation of denervated muscle resulted in higher oxidative enzyme activities. Furthermore, single fibre analyses for succinate dehydrogenase showed a more uniform distribution of activity in stimulated-denervated muscle when compared to normal muscle. As was also the case following stimulation of innervated muscle, glycolytic enzymes were decreased in activity and the LDH-isozyme pattern was also shifted towards heart type. No change of the myosin light chain pattern could be observed after 56 days of stimulation.
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PMID:Changes of energy metabolism, myosin light chain composition, lactate dehydrogenase isozyme pattern and fibre type distribution of denervated fast-twitch muscle from rabbit after low frequency stimulation. 406 81

Glial and Schwann cells undergo marked biochemical and morphological alterations following axonal injury. In the present experiments, the extent of enzyme activity associated with anaerobic (LDH, lactic dehydrogenase) vs aerobic (SDH, succinic dehydrogenase) respiration was assessed distal to the site of nerve fiber injury. Studies were performed in rat central (optic) and peripheral (sciatic) nerves at 2, 7 and 14 days postoperatively (d.p.o.). In sciatic nerves, LDH activity rose 3-fold in traumatized (vs unoperated control) nerve tissue between 2 and 7 d.p.o. and remained elevated at 14 d.p.o. SDH activity in traumatized nerve was equal to that in unoperated nerve at 7 d.p.o., but decreased at 14 d.p.o. LDH activity in optic nerve at 2 d.p.o. was equivalent to that in control nerve, but rose approximately two-fold by 7 d.p.o. However, unlike peripheral nerve, activity in traumatized optic nerve decreased to control levels at 14 d.p.o. SDH activity in traumatized optic nerve remained unchanged at any timepoint examined. Taken in concert, these data are consistent with the hypothesis that there is an overall shift in CNS glial and Schwann cell metabolism from aerobic to anaerobic respiration following nerve injury. Additional studies were performed to determine if this shift requires prior Schwann or glial cell mitosis. Administration of mitotic inhibitor (AraC, cytosine arabinofuranoside) inhibited post-traumatic elevations in LDH activity in optic, but not peripheral nerve. No significant effect of the drug on axonal degeneration (as assessed by saxitoxin binding) was observed.
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PMID:The role of post-traumatic mitosis in elevation of anaerobic metabolism enzyme (lactic acid dehydrogenase) activity in degenerating central and peripheral nerve. 407 42

1. The kinetic and metabolic properties of lactate dehydrogenase isoenzyme LDH(x) from human sperm cells and rat testes were studied. 2. LDH(x) shows a sensitivity to inhibition by stilboestrol diphosphate, urea and guanidinium chloride different from that of the LDH-H(4) and LDH-M(4) isoenzymes. 3. About 10 and 20% of the total lactate dehydrogenase activity of testes and sperm cells respectively were associated with particulate fractions. In sperm cells 11% was localized in the middle piece and 18.8% in the head fraction. LDH(x) was found in all particulate fractions of sperm cells. The middle piece contained 41.0% of total LDH(x) activity and showed high succinate dehydrogenase activity. 5. The pH-dependence of lactate/pyruvate and NAD(+)/NADH concentration ratios were estimated. Lactate dehydrogenase in sperm cells has maximal activity with NADH as coenzyme at pH7.5 and with NADPH as coenzyme at pH6.0. At pH6.0 a 10% greater oxidation of NADPH than of NADH was found. At acid pH lactate hydrogenase may function as an enzyme bringing about transhydrogenation from NADPH to NAD(+). 6. In agreement with the stoicheiometry of the lactate de- hydrogenase reaction, the lactate/pyruvate concentration ratio decreased with increasing pH. 7. The lactate/pyruvate and NAD(+)/NADH concentration ratios were estimated with glucose, fructose and sorbitol as substrates and as a function of time after addition of these substrates. During a 20min. period after the addition of the substrates, changes in lactate/pyruvate and NAD(+)/NADH concentration ratios were noticed. Increasing concentration of the substrates mentioned gave rise to asymptotic increases in lactate and pyruvate. 8. Sorbitol did not act as a substrate for LDH(x). 9. The findings described are consistent with the idea that LDH(x) is different from other known lactate dehydrogenase isoenzymes, but that it has a metabolic function similar to that of the isoenzymes of other tissues.
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PMID:Lactate dehydrogenase isoenzymes of sperm cells and tests. 430 63

Alterations in enzyme activities involved in muscle energy metabolism and the muscle fiber type distribution were investigated in six subjects, ranging in age from 19-23 years, following short-term, high intensity exercise. Changes in the vastus lateralis muscle were studied prior to exercise and approximately 24 h after each of 2 consecutive days of supramaximal cycling exercise (120% VO2 max) performed intermittently as 1-min work to 4-min rest until fatigue or until 24 repetitions had been completed. The results indicated that there were no changes (P greater than 0.05) in maximal in vitro activities for representative enzymes of beta-oxidation (3-hydroxyacyl CoA dehydrogenase, HAD), the citric acid cycle (succinic dehydrogenase, SDH), glucose phosphorylation (hexokinase, HK), glycogenolysis (total phosphorylase, PHOSPH), or glycolysis (phosphofructokinase, PFK; pyruvate kinase, PK; lactate dehydrogenase, LDH) in spite of the large increase in carbohydrate utilization and glycolytic flux rate. In addition, although no change in fiber type distribution was found in the pre-exercise biopsy between days, an acute reduction (P less than 0.05) in type I fiber distribution occurred with exercise. It is concluded that supramaximal exercise performed on a short-term basis does not alter the enzymatic profile or the fiber type distribution when measured 24 h following the activity.
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PMID:Fiber type distribution and maximal activities of enzymes involved in energy metabolism following short-term supramaximal exercise. 609 Mar 24


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