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)

We studied functional disturbances following left middle cerebral artery occlusion in rats. Neuronal function was evaluated by [14C]2-deoxyglucose autoradiography 1 day after occlusion. We analyzed the mechanisms of change in glucose utilization outside the infarct using Fink-Heimer silver impregnation, axonal transport of wheat germ agglutinin-conjugated-horseradish peroxidase, and succinate dehydrogenase histochemistry. One day after occlusion, glucose utilization was remarkably reduced in the areas surrounding the infarct. There were many silver grains indicating degeneration of the synaptic terminals in the cortical areas surrounding the infarct and the ipsilateral cingulate cortex. Moreover, in the left thalamus where the left middle cerebral artery supplied no blood, glucose utilization significantly decreased compared with sham-operated rats. In the left thalamus, massive silver staining of degenerated synaptic terminals and decreases in succinate dehydrogenase activity were observed 4 and 5 days after occlusion. The absence of succinate dehydrogenase staining may reflect early changes in retrograde degeneration of thalamic neurons after ischemic injury of the thalamocortical pathway. Terminal degeneration even affected areas remote from the infarct: there were silver grains in the contralateral hemisphere transcallosally connected to the infarct and in the ipsilateral substantia nigra. Axonal transport study showed disruption of the corticospinal tract by subcortical ischemia; the transcallosal pathways in the cortex surrounding the infarct were preserved. The relation between neural function and the neuronal network in the area surrounding the focal cerebral infarct is discussed with regard to ischemic penumbra and diaschisis.
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PMID:Neuronal network disturbance after focal ischemia in rats. 247 23

Changes in the activity of three mitochondrial enzymes in rat liver after in vitro ischemia have been determined by enzyme histochemical methods. The changes were correlated with the appearance in the electron microscope of flocculent densities in the mitochondria indicative of irreversible cell injury. The flocculent densities were observed in rat liver after about 2 h of ischemia in vitro at 37 degrees C. At the same time the activity of glutamate dehydrogenase, localized in the mitochondrial matrix, started to decrease. However, the activities of succinate dehydrogenase localized in the inner membrane of mitochondria, as well as monoamine oxidase of the mitochondrial outer membrane did not change at that stage. It is concluded from the results of this study and those of others that flocculent densities are formed by denaturation of proteins of the mitochondrial matrix in which glutamate dehydrogenase takes part. It should be considered more as a sign than as the cause of cell death.
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PMID:A histochemical study of changes in mitochondrial enzyme activities of rat liver after ischemia in vitro. 287 57

A homogeneous group of six patients, who underwent coronary artery bypass surgery, was studied to determine the presence of oxidative stress caused by oxygen-derived free radicals and its relationship with reperfusion cell damage. Biopsies were performed before ischemia and 10 minutes after reperfusion. The samples were assayed for hydroperoxide-initiated chemiluminescence and histochemical succinic dehydrogenase activity; the specimens were also studied by electron microscopy. The preischemic biopsy specimens showed chemiluminescence of 40 +/- 2 (cpm/mg protein) x 10(3), normal succinic dehydrogenase activity (grade 4), and generally preserved ultrastructure (necrotic/normal cells 5/100). However, the reperfusion biopsy specimens showed an increase in chemiluminescence to 91 +/- 19 (cpm/mg protein) x 10(3) (p less than 0.025), a partial loss of enzymatic activity (grade 2.6), and ultrastructural changes characterized by mitochondrial swelling and focal myofibrillar disorganization (necrotic/normal cells: 15/100; p less than 0.001). These observations seem to indicate the presence of oxidative stress during reoxygenation, a situation that may play a major role in the genesis of reperfusion injury. It appears to be the first observation relating free radical-induced oxidative stress to reperfusion injury in humans.
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PMID:Assessment of myocardial oxidative stress in patients after myocardial revascularization. 334 Nov 66

It has been demonstrated that perfusion of myocardium with glutamic acid or tricarboxylic acid cycle intermediates during hypoxia or ischemia, improves cardiac function, increases ATP levels, and stimulates succinate production. In this study isolated adult rat heart cells were used to investigate the mechanism of anaerobic succinate formation and examine beneficial effects attributed to ATP generated by this pathway. Myocytes incubated for 60 min under hypoxic conditions showed a slight loss of ATP from an initial value of 21 +/- 1 nmol/mg protein, a decline of CP from 42 to 17 nmol/mg protein and a fourfold increase in lactic acid production to 1.8 +/- 0.2 mumol/mg protein/h. These metabolite contents were not altered by the addition of malate and 2-oxoglutarate to the incubation medium nor were differences in cell viability observed; however, succinate release was substantially accelerated to 241 +/- 53 nmol/mg protein. Incubation of cells with [U-14C]malate or [2-U-14C]oxoglutarate indicates that succinate is formed directly from malate but not from 2-oxoglutarate. Moreover, anaerobic succinate formation was rotenone sensitive. We conclude that malate reduction to succinate occurs via the reverse action of succinate dehydrogenase in a coupled reaction where NADH is oxidized (and FAD reduced) and ADP is phosphorylated. Furthermore, by transaminating with aspartate to produce oxaloacetate, 2-oxoglutarate stimulates cytosolic malic dehydrogenase activity, whereby malate is formed and NADH is oxidized. In the form of malate, reducing equivalents and substrate are transported into the mitochondria where they are utilized for succinate synthesis.
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PMID:Evidence for succinate production by reduction of fumarate during hypoxia in isolated adult rat heart cells. 342 43

To evaluate the diagnostic role of histochemically demonstrated aerobic dehydrogenases in ischemic myocardial injury NADH-diaphorase, succinate dehydrogenase (SDH), beta-hydroxybutyrate dehydrogenase (HBDH) and malate dehydrogenase (MDH) were demonstrated histochemically and the corresponding enzyme activities were measured biochemically in isolated perfused rats hearts after global ischemia from 0 to 12 h. The present data show that the enzyme-histochemical methods when used properly are more sensitive indicators of early ischemic injury than classical histological staining procedures. From the enzymes tested here the histochemical demonstration of HBDH turned out to be best suited for use when suspecting ischemic myocardial injury at autopsy.
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PMID:Oxidative enzyme activities and respective histochemical reactions in ischemic rat myocardium. 342 4

Poly- and monoclonal antibodies to neoantigens of the human C5b-9 complement complex, as well as polyclonal antibodies to C5, C8, and C9, were used to detect and identify C5b-9 deposits in human myocardial tissue. Immunocytochemical studies were performed on fresh-frozen autopsy material derived from patients with myocardial infarctions; in addition, in 17 of these patients, paraffin sections of formalin-fixed tissue were investigated. Sixteen autopsies from patients with noncardiac diseases were analyzed as controls. Without exception, C5b-9 positivity was registered selectively and exclusively on and in myocardial cells located within the zones of infarction. The selectivity of staining was confirmed by control reactions for succinic dehydrogenase activity performed in adjacent, respective double-stained sections. Most intensive staining with anti-neoantigen antibodies was observed in the peripheral areas of the infarctions. Weak staining for C3d, rather strong staining for C5 and C9, and intermediate staining with anti-C8 antibodies were observed in the same localizations. Stainings for C4 and IgA were negative, whereas immunocytochemical reactions for IgG and IgM revealed an irregular and very weak staining. Only very weak staining was also observed with a monoclonal antibody to complement S-protein, indicating that the terminal complement components were deposited mainly in the form of membrane-damaging C5b-9 complexes. Immunocytochemical staining for C5b-9 was found to represent a most sensitive tool for detection of ischemic myocardial lesions, permitting easy detection even of single cell necroses. As a working hypothesis, we suggest that initial ischemia may cause loss of the ability of the heart muscle cells to regulate complement turnover at the membrane level. The resulting deposition of C5b-9 on the cell membranes may contribute to functional disturbance and irreversible damage of myocardial cells during the infarction process.
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PMID:Deposition of the terminal C5b-9 complement complex in infarcted areas of human myocardium. 352 91

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 results of quantitative histoenzymologic investigations of succinate dehydrogenase, lactate dehydrogenase and NAD-diaphorase in cardiomyocytes of dogs with acute experimental arterial occlusion in ischemic and postischemic periods are reviewed. An increased activity of dehydrogenases in the early periods (3,6 h) of ischemia and during recirculation was established, with its noticeable reduction at later terms (9,12 h). Medical correction of postischemic disorders was shown to improve cardiomyocyte metabolism.
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PMID:[Changes in the dehydrogenase activity of cardiomyocytes during acute experimental arterial occlusion of extremities]. 373 May 53

Histochemical study of enzymatic activity in the myocardium was performed in sudden cardiac death. Human hearts in which there were no macroscopic and histological focal or diffuse changes served as material. The following enzymes were studied in the anterior or posterior walls of the left ventricle or in the interventricular septum: succinate dehydrogenase, lactate dehydrogenase (LDH), beta-hydroxybutyrate dehydrogenase (OHBDH), alpha-glycerophosphate- and glucose-6-phosphate dehydrogenase, NAD-diaphorase and phosphorylase. Increased activity of OHBDH and LDH was found: 36,0 and 22,6% higher than in trauma and brain hemorrhage that served as control. These alterations seem to be connected with the increase of blood content of fatty acids, and lactate as a response to the catecholamine excess. Foci of an acute ischemia were found in the interventricular septum in 80% of cases in which phosphorylase was revealed. The appearance of the ischemic foci was obviously due to the coronary arteries contraction.
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PMID:[Histoenzymological characteristics of the myocardium in sudden cardiac death]. 405 12

The authors carried out histochemical determinations of the glycogen level and the activity of some enzymes controlling carbohydrate metabolism (glycogen transferase and phosphorylase, succinate dehydrogenase) in the lumbar segments of the spinal cord of 40 animals (cats) with circulatory ischemia caused by aorta ligation. The examinations were performed at different periods of time after the ischemia induction under conditions of carbohydrate load. In the course of the pathological process development because of the ischemia (within a period ranging from 6 hours to 26 days) considerable variations of the glycogen-synthetizing capacities of the spinal cord nervous elements were revealed. These variations were of a periodic character. The number of glycogen-containing cells was maximal within a period ranging from the 2nd to the 10th day: this correlated with the highest enzymatic activity in this period. The glycogen content in a cell and the degree of the latter's damage were found to be in an inverse relationship. It is shown that different resistance of the nervous elements to hypoxia is determined to a great measure by their capacity to synthetize and deposit glycogen. Thus, the glycogen metabolism, being a specific compensatory-adaptive mechanism of the nervous tissue, is, thereby, a material basis of its vital activity.
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PMID:[Glycogen metabolism of neuronal systems of the spinal cord in experimental ischemia]. 617 33


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