Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.4.1.2 (glutamate dehydrogenase)
4,380 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mammalian and avian muscles were examined histochemically and biochemically to determine the relative contribution of membrane bound (mitochondrial and sarcotubular) ATPases under the same conditions employed for myofibrillar ATPase. For histochemically investigated Ca+(+)-ATPase activity following incubation at pH 9.4 according to the calcium-citro-phosphate technique, avian muscle displayed distinct mitochondrial localization in both dark and light staining fibres. However, mitochondrial localization did not occur in mammalian muscle fibres. Pretreatment of unfixed frozen sections with ouabain, cyanide and acetone did not prevent the reticular distribution in avian muscle fibres. The present study demonstrates that "myofibrillar" localization is achieved by the Ca+(+)-precipitation technique: provided frozen sections are pretreated with cold acetone, fixed in a fixative containing oligomycin or azide and then incubated in a medium containing glycine-NaO H as buffer. Mitochondria prepared by successive mechanical homogenization or by Nagarse treatment plus 2 min homogenization develop different ATPase activities at pH 9.4 7.4 6.0 and 4.35 as well as stimulation by 70 mM Ca++ at these pHs compared to those ATPase activities in the homogenate of mixed hamster hind leg muscles. Glycerol-3-phosphate dehydrogenase and creatine kinase (both located at the outer surface of the inner mitochondrial membrane) and succinate dehydrogenase and glutamate dehydrogenase (localized at the inner mitochondrial membrane and in the matrix resp.) also show different activities in both mitochondria preparations indicating different membrane properties of both mitochondria. Evidence is obtained that using the calcium-citro-phosphate technique at pH 9.4 oligomycin-sensitive and -insensitive ATPases are activated by Ca++ in both mitochondria preparations. Since in muscle homogenate less than 10% of Ca+(+)-stimulated ATPase activity is oligomycin-sensitive, mitochondrial ATPase exhibit only a small portion of total ATPase from mixed hamster hind leg muscles.
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PMID:Histochemical and biochemical investigations of adenosine triphosphatase in vertebrate mixed muscles. 4 33

The activities of eight enzymes (glutamate dehydrogenase, sorbital dehydrogenase, malate dehydrogenase, lactate dehydrogenase, alpha-hydroxy butyrate dehydrogenase, gamma-glutamyl transpeptidase, alkaline phosphatase and creatine kinase) were determined in tissue homogenates of liver, kidney, spleen, lung, small intestine, cardiac muscle and skeletal muscle, from 15 Large White pigs of three different ages (1.5 weeks, 18--22 weeks and 113 weeks). The results showed that variation in tissue enzyme concentration due to differences in sex is minimal. Variation due to differences in age, however, appears to be of greater importance, particularly when considering young animals. These age differences may affect the interpretation of plasma enzyme changes due to tissue damage, and the use of additional enzyme assays as an aid to interpretation in these cases is advisable.
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PMID:Enzyme activities in tissues of clinically normal Large White pigs. Variations with age and sex. 60 99

The method for the determination of enzymic activity in turbid, lipaemic sera, which involves clearing by polyanion precipitation with heparin and magnesium chloride, was critically reviewed. In the diagnosis of diseases of the liver and pancreas, which are frequently associated with hyperlipoproteinaemia, only residual enzyme activities are measured in the cleared serum after polyanion treatment. In the measurement of glutamate dehydrogenase and in the Phadebas test for alpha-amylase, the enzymes are inactivated by treatment with heparin and magnesium chloride. On the other hand, as a result of polyanion precipitation gamma-glutamyl transferase is transferred, together with lipoproteins and chylomicrons, to the lipid-rich supernatant. Acid phosphatase also exhibits only residual activity in cleared serum. The activity of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, leucine arylamidase, cholinesterase, creatine kinase, lactate dehydrogenase, and alpha-hydroxybutyrate dehydrogenase, and the activity of alpha-amylase in the Merckotest are not affected by polyanion treatment of the serum.
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PMID:[Enzyme diagnosis in lipaemic sera before and after polyanion precipitation with heparin and magnesium chloride (author's transl)]. 92 35

The rate of distribution of cell enzymes between the intravascular and extravascular space was studied, following a sudden decrease of enzyme activities in plasma. This rapid decrease of enzyme activities was achieved in rats by a rapid exchange of the blood with a twofold volume of a suspension of homologous erythrocytes in isoosmolar bovine serum albumin solution. After this plasmapheresis, the activities of seven cell enzymes in the plasma were decreased to 14 to 22% of their original values. The subsequent increase in activities showed different kinetics, depending on the enzyme. After 120 min, creatine kinase had reached the starting activity; malate dehydrogenase and aldolase reached their original activities after 180 min. Aspartate aminotransferase, glutamate dehydrogenase, alanine aminotransferase and pyruvate kinase increased more slowly and they had still not reached their starting values after 240 min. Repetition of the plasmapheresis after 90 min had no obvious effect on the kinetics of the subsequent activity increase. During the first minutes after plasmapheresis the adjustment of the activity equilibrium between the interstitial and the intravascular compartments depends mainly on the capillary permeability. It is therefore possible to determine half-life constants for the distribution of enzymes within the extracellular space. The constants for malate dehydrogenase and aldolase are almost identical with those determined by intravenous injection, whereas there are discrepancies in the constants for the remaining enzymes. The constants for pyruvate kinase and glutamate dehydrogenase are significantly lower, while those for aspartate aminotransferase, alanine aminotransferase and creatine kinase are significantly higher, than those determined after intravenous injection. Possible reasons for these differences are disucssed.
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PMID:[Plasmapheresis as an experimental model for studies on the extracellular distribution of enzymes. Distribution and transport of cell enzymes within the extracellular space. IV (author's transl)]. 93 47

Because of the difficulties in drawing blood for clinical chemistry in small laboratory animals there exist many methods for sampling blood and the preparation of serum, none of which is generally accepted or well standardised. It was the aim of this study to investigate the effects of sampling techniques on normal values of enzyme activities in the serum of rat and mouse. The activities of the following enzymes were determined: sorbitol dehydrogenase, lactate dehydrogenase, malate dehydrogenase, glutamate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, pyruvate kinase, creatine kinase, myokinase, alkaline phosphatase and leucine aminopeptidase. In addition plasmaproteins, urea and inorganic phosphorus were measured. In rats blood was obtained from the following sites: retroorbital venous plexus, jugular vein, heart and ventral aorta. In mice blood was sampled from the jugular vein and the ventral aorta. Shifts of water from the interstitial to the intravascular space due to hypovolemia occurring during the experimental procedure were followed up by measuring the hematocrit and the distribution of radioiodide labelled albumin. In rats the activities of lactate dehydrogenase, malate dehydrogenase, aspartate aminotransferase, pyruvate kinase, creatine kinase and myokinase found in blood serum obtained from the retroorbital venous plexus and the ventral aorta were too high compared to the other sampling sites. Activities of alkaline phosphatase and alanine aminotransferase were slightly elevated when blood was sampled from the punctured retroorbital venous plexus. Small differences in plasmaproteins and hematocrit values were found to be due to acute shifts of water within the extracellular space. In mice the activities of lactate dehydrogenase, malate dehydrogenase, aspartate aminotransferase and myokinase were found to be too high in blood serum obtained from the ventral aorta. Efflux of enzymes from damaged cells and the interstitial space ive caused erroneous results too, but only to a minor extent. The most reliable method for blood sampling in rat and mouse is the cannulation of the jugular vein. The heart puncture can be recommended too. Attention should be paid, however, to the possibility of aspirating disrupted muscle cells through the inserted needle.
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PMID:[Effects of blood sampling on enzyme activities in the serum of small laboratory animals (author's transl)]. 108 84

This study was prompted by the paradox of strong presence of mitochondria in an anaerobic protozoan, recently reclassified from the yeasts. Stemming from publication in 1911 to 1912, Blastocystis hominis has been generally accepted as a harmless intestinal yeast of humans, with short standardized textbook (parasitology) descriptions, even to the present day. Reports since 1967 have changed the classification of B. hominis from yeast to protozoan (Sarcodina), and this has been followed by interest in B. hominis-caused disease, resulting in documentation of disease in humans and other primates. In this study of B. hominis, the basic ultrastructure of the mitochondria was shown by thin-section electron microscopy to be identical to that of an archetypical mitochondrion. There were hundreds of them in large B. hominis cells (100 to 200 microns in diameter). Mitochondria were confined to a peripheral ring of cytoplasm bounded by the outer cell membrane (there is no cell wall) and the membrane of the large, spherical, organelle-free central body that constitutes 75% of the cell's volume. Mitochondria tended to surround the cell's usual two to four nuclei. Rhodamine 123 stained the mitochondria selectively, visualized by fluorescence microscopy. The cell was devoid of cytochromes. Addition of 0.1% cytochrome c to the growth medium increased utilization of glucose by 34% and that of lactate by 17%. Furthermore, it markedly increased the number of mitochondrion-filled cells. At higher concentrations, cytochrome c inhibited the growth of the cells. Despite the presence of large numbers of mitochondria, activities of the mitochondrial enzymes pyruvate dehydrogenase complex, alpha-ketoglutarate dehydrogenase complex, isocitrate dehydrogenase, glutamate dehydrogenase, and cytochrome c oxidase were absent. Thus, the function of the mitochondria in B. hominis remains unknown. Considerable activities of aspartate aminotransferase and alanine aminotransferase were found. Aldolase activity was prominent. Pyruvate decarboxylase was present. Diaphorase and lactate dehydrogenase were detectable but in suspect quantities. Other missing enzymes were gamma glutamyl transpeptidase, alkaline phosphatase (a lysosomal marker), and creatine kinase isoenzymes.
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PMID:Biochemical and ultrastructural study of Blastocystis hominis. 283 9

An atypical creatine kinase (CK) isoenzyme migrating cathodically to CK-MM in the electrophoresis was observed as response to the embolization of the right hepatic artery in two patients with liver metastasis. The time course of the atypical CK release was compared to that of tumor secretion products, i.e., insulin and 5-hydroxy-in-dol-acetic acid. The CK isoenzyme probably reflects a mitochondrial breakdown of the metastasis in question. The influence of the treatment on liver function was characterized by a marginal augmentation of ASAT and ALAT and by a small but significant leakage of mitochondrial glutamate dehydrogenase. In addition to the atypical CK, CK-BB, and CK-MB isoenzymes were found in the serum of the patient with primary carcinoid carcinoma.
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PMID:Creatine kinase isoenzymes: biochemical findings after therapeutical embolization of the hepatic artery in two patients with liver metastasis of an islet cell carcinoma or a carcinoid tumor. 298 64

The assay of cerebrospinal fluid (CSF) enzymes has been suggested for assessing the extent of damage and patient prognosis in cases of brain injury. A potential difficulty associated with using CSF enzyme levels as predictors of outcome is the possibility that enzyme concentrations may vary substantially from one brain region to another. We have determined the concentrations of seven enzymes in seven brain regions in the rat and cat. Acid phosphatase (ACP), aspartate aminotransferase (AST), isocitrate dehydrogenase (ICDH), lactate dehydrogenase (LD), and malate dehydrogenase (MDH) show little regional variability in the rat and cat while creatine kinase (CK) and glutamate dehydrogenase (GDH) both exhibit considerable regional variability in both animals. Lack of correlation between CSF enzyme levels and prognosis may possibly be explained by the observed regional variability. The enzymes demonstrating more homogeneous concentrations throughout the brain may be better candidates for predicting patient outcome by determination of the CSF enzyme level.
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PMID:The regional variability of enzymes in the brain: relevance to CSF enzyme determinations. 341 84

The catalytic activity of up to fifteen enzymes was investigated in the liver, heart, skeletal muscle, kidney (medulla, cortex), brain, lung, duodenum, spleen and pancreas from man and animals. Human specimens were obtained from autopsies and immediately post-mortem from dogs, rabbits, guinea pigs, rats and mice. The differences between our results and previous reports of considerably lower activities for structural enzymes (e.g. creatine kinase) and for enzymes partly of mitochondrial origin (e.g. glutamate dehydrogenase, aspartate aminotransferase, malate dehydrogenase), is attributed to our use of a detergent extraction technique. The superiority of the detergent technique with regard to enzyme yield is exemplified by a comparison of various methods of extraction in rat liver, heart and skeletal muscle. Use of standardized assays allows a qualitative inter-species comparison of results. The influence of autolysis on catalytic activity of human autopsies is considered of minor importance.
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PMID:Catalytic enzyme activity concentration in tissues of man, dog, rabbit, guinea pig, rat and mouse. Approach to a quantitative diagnostic enzymology, III. Communication. 370 Dec 70

Using fully mechanized analytical equipment, interference by haemolysis in the determination of 26 clinical chemical parameters was determined quantitatively by adding haemolysate to serum. Haemoglobin concentrations up to 6.6 g/l caused essentially no interference in the following determinations: albumin (immuno-nephelometric), alpha-amylase, calcium, chloride, cholesterol, cholinesterase, creatinine, iron, glucose, glutamate dehydrogenase, uric acid, urea, sodium, inorganic phosphate, total protein, transferrin and triglycerides. In the presence of haemoglobin, erroneously high values were found for: lactate dehydrogenase (haemoglobin higher than 0.2 g/l), aspartate aminotransferase, potassium and acid phosphate (haemoglobin higher than 1.5 g/l), creatine kinase (haemoglobin higher than 2.5 g/l) and alanine aminotransferase (haemoglobin higher than 3.4 g/l). Erroneously low values were found for bilirubin (haemoglobin higher than 0.8 g/l), alkaline phosphatase and albumin (by electrophoresis) (haemoglobin higher than 1.5 g/l) and gamma-glutamyltransferase (haemoglobin higher than 3.0 g/l).
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PMID:Haemolysis as an interference factor in clinical chemistry. 371 97


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