Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:1.4.1.2 (glutamate dehydrogenase)
4,380 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tissue culture for one or seven days of pancreatic islets isolated from 21-day old fetal rats was found to be associated with a marked increase in the oxidation of L-(U-14C) glutamine by intact islets and in the activity of both alanine-glutamate and aspartate-glutamate transaminases as well as glutamate dehydrogenase in islet homogenates. This coincided with an increase in the relative amount of mitochondrial DNA. The activities of glucose-phosphorylating enzymes (hexokinase and glucokinase), glyceraldehyde-3-phosphate dehydrogenase and lactate dehydrogenase were less markedly increased during the culture period than those of enzymes involved in amino acid catabolism and located, in part at least, in mitochondria. The combined data suggest that the functional maturation of fetal islets during the culture period is associated with and may be attributable to a preferential maturation of their mitochondria.
...
PMID:Maturation of fetal rat islet cells in vitro during tissue culture is associated with increased mitochondrial function. 213 6

The alterations of several small-intestinal mucosal enzymes have been examined in cats that underwent different periods (1-4 hr) of occlusion of the superior mesenteric artery, followed by 4 hr of reperfusion. The damage progressed during ischemia and reperfusion from the villus tips to the crypts: first, there was a rapid decrease in the activity of maltase, a brush-border enzyme; a slower decline occurred in two cytoplasmic enzymes, aldolase A (with preferential location in feline villus cells) and lactate dehydrogenase (with an ubiquitous distribution); a lag preceded the decrease in aldolase B (a cytoplasmic enzyme shown to occur mainly in feline crypt cells). For all these enzymes, the initial period of reperfusion was associated with a greater decrease in enzyme activity than persisting ischemia. By determination of the unsedimentable proportion of glutamate dehydrogenase (a mitochondrial matrix enzyme) and of acid phosphatase (a lysosomal enzyme) it was demonstrated that ischemia caused important mitochondrial damage before the cells were lost, whereas no lysosomal damage was observed in any condition. These sensitive parameters of cell damage can serve as a criterion for an adequate evaluation of potential cytoprotective agents.
...
PMID:Influences of ischemia and reperfusion on the feline small-intestinal mucosa. 219 34

A radioisotopic method for the assay of reduced or oxidized pyridine nucleotides, based on the interconversion of 2-[U-14C]ketoglutarate or 2-keto[3,4-3H]glutarate and labelled L-glutamate in the reaction catalyzed by glutamate dehydrogenase, was applied to the measurement of lactate dehydrogenase activity in rat pancreatic islet homogenates. Using the tritiated tracer, the limit of sensitivity of the procedure for NAD(P)H assay was close to 1.0 fmol/sample, and lactate dehydrogenase activity could be measured in as little as 0.0005 islet/sample i.e., at a single cell level. This radioisotopic procedure, which can be used for the assay of various metabolites and enzymic activities, thus provides a tool for investigating the heterogeneity in metabolic behaviour of individual cells.
...
PMID:Radioisotopic measurement of femtomolar amounts of NAD(P)H in the assay of enzymatic activity at a single cell level. 220 May 24

The hepatotoxic and lipid peroxidative potentials of t-butyl hydroperoxide (t-BuOOH) towards isolated perfused rat livers were investigated at doses of 1 and 3 mmol l-1. t-BuOOH led to a concentration-dependent release of cytosolic (glutamate-pyruvate transaminase and lactate dehydrogenase) and mitochondrial (glutamate dehydrogenase) enzymes, an accumulation of calcium in the liver, a marked depletion of hepatic glutathione and an enhanced release of it into the perfusate, as well as an enhanced formation and release of malondialdehyde (MDA) by the liver. These effects were blocked in the presence of the potent iron chelator deferrioxamine, and enhanced in livers from iron-overloaded as well as in livers from glutathione-depleted rats. Our results indicate that the hepatotoxic and pro-oxidant actions of organic hydroperoxides depend upon the presence of ionized iron as a catalyst of radical-forming breakdown reactions, and are potentiated by impairment of glutathione-dependent detoxification reactions.
...
PMID:The role of iron and glutathione in t-butyl hydroperoxide-induced damage towards isolated perfused rat livers. 225 82

Treatments with copper sulphate (CuSO4), paraquat (PQ) and methidathion (MD) caused tissue damage and stress effects in carp, indicated by the increased lactate dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT), and glutamate dehydrogenase (GIDH) enzyme activities and elevated blood-sugar levels. Copper sulphate, administered together with PQ and MD, were synergistic in terms of tissue damage and stress effects. The isoenzyme patterns showed organ-specific tissue damage. The administered chemical and isoenzymes indicating liver damage were detectable in the blood. The combination of CuSO4 and MD caused focal cell necrosis, which was observable in the liver tissue by light microscopy. Electron microscopic studies revealed the presence of damaged parenchymal cells with electron transparent cytoplasms, myelin figures, and altered mitochondria ER and Golgi.
...
PMID:The effects of pesticides on some biochemical parameters of carp (Cyprinus carpio L.). 232 21

Ehrlich ascites tumor cells were permeabilized using low concentrations of digitonin, 8 micrograms/10(6) cells. Permeabilization was monitored by the assay of lactate dehydrogenase released into the incubation medium and of hexokinase partially bound to mitochondria. Integrity of the cellular organelles was unaffected as determined by assay of the mitochondrial enzyme glutamate dehydrogenase. Cells were stained with rhodamine 123 as a mitochondrial specific dye and propidium iodide/mithramycin as DNA specific dyes. The green fluorescence of bound rhodamine 123 versus red fluorescence of DNA in individual cells was analysed by dual parameter flow cytometry. Incubation of cells with inhibitors of mitochondrial energy metabolism, such as, potassium cyanide and carbonyl cyanide m-chlorophenylhydrazone abolished binding of rhodamine 123. Flow cytometric data allowed a correlation between cell position in the mitotic cycle with total mitochondrial activity. In addition, comparison of the characteristics of propidium iodide and ethidium bromide staining further elucidated the molecular basis of the staining with the positively-charged fluorescent dye rhodamine 123.
...
PMID:Simultaneous analysis of mitochondrial activity and DNA content in Ehrlich ascites tumor cells by dual parameter flow cytometry. 248 81

This paper concerns an enzymological investigation into a putative feline analogue of the human autosomal recessive disease primary hyperoxaluria type 2. The hepatic activities of D-glycerate dehydrogenase, using both D-glycerate and hydroxypyruvate as substrates, and glyoxylate reductase, which are the deficient enzyme activities in human primary hyperoxaluria type 2, were markedly depleted in four affected cats (0-6% of controls). The activities of a number of other enzymes, lactate dehydrogenase, glutamate dehydrogenase, D-amino acid oxidase, aspartate:2-oxoglutarate amino-transferase, glutamate:glyoxylate aminotransferase and alanine:glyoxylate aminotransferase (the deficient enzyme in primary hyperoxaluria type 1) were unaltered. The intracellular distribution of D-glycerate dehydrogenase and glyoxylate reductase in cat liver was shown to be cytosolic, as they are in human liver. The activities of D-glycerate dehydrogenase and glyoxylate reductase were determined in unaffected related cats and putative heterozygotes were identified. The correlation between D-glycerate dehydrogenase and glyoxylate reductase activities in the related cats and their combined deficiency in the affected cats confirmed previous suggestions that they are identical gene products.
...
PMID:Enzymological characterization of a feline analogue of primary hyperoxaluria type 2: a model for the human disease. 251 73

The effect of Ca2+-homopantothenate (HOPA) treatment (250 mg/kg for 5 d) has been studied by evaluating the specific activity of enzymes related to: glycolytic pathway (hexokinase, phosphofructokinase, pyruvate kinase, lactate dehydrogenase), tricarboxylic acid cycle (citrate synthase, malate dehydrogenase), mitochondrial electron transfer chain (succinate dehydrogenase, cytochrome oxidase), NADH redox state (NADH cytochrome c reductase), acetylcholine metabolism (acetylcholinesterase), and glutamate metabolism (glutamate dehydrogenase). The enzymatic activity assays were performed on homogenate in toto, nonsynaptic mitochondria and synaptosomes isolated from: cerebral cortex, hippocampus, striatum, hypothalamus, medulla oblongata, and cerebellum of normoxic rats and rats submitted to intermittent normobaric hypoxia (90:10, N2:O2). In normoxic rats, HOPA was unable to induce any modification. Hypoxia per se induced a decrease in the activity of synaptosomal cytochrome oxidase in cerebral cortex, hippocampus, and cerebellum.
...
PMID:Effect of Ca2+-homopantothenate and mild hypoxia on some enzyme activities evaluated in subcellular fractions from different rat brain regions. 254 16

The activity of dipeptidyl aminopeptidase IV was studied in the sera of 378 hospitalized patients. The mean activity of dipeptidyl aminopeptidase IV was elevated significantly in patients with neoplasmata and hepatitis, but not in patients with liver cirrhosis. Significant correlations (p less than 0.001) existed with gamma-glutamyl transferase, glutamate dehydrogenase, alkaline phosphatase and leucine aminopeptidase. A significant correlation with lactate dehydrogenase existed only in patients with neoplasmata. Principal component analysis, performed with aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, leucine aminopeptidase, lactate dehydrogenase and dipeptidyl aminopeptidase IV, revealed correlations between the activities of aspartate aminotransferase and alanine aminotransferase, and between alkaline phosphatase and leucine aminopeptidase, but neither dipeptidyl aminopeptidase IV nor lactate dehydrogenase showed any correlation with either of these two groups. In lectin affinity chromatography with concanavalin A and wheat germ lectin sepharose, serum dipeptidyl aminopeptidase IV from liver cirrhosis patients showed the same binding pattern as that from healthy subjects. The activity and glycosylation of dipeptidyl aminopeptidase IV in serum and hepatic plasma membranes was investigated in rats, following the induction of hepatitis with galactosamine. In the serum, dipeptidyl aminopeptidase IV activity was elevated as early as 6 h after galactosamine injection, and the elevated activity persisted until the 7th day. At the same time dipeptidyl aminopeptidase IV activity was also elevated in the hepatic plasma membrane. Ninety eight percent of hepatic dipeptidyl aminopeptidase IV bound to concanavalin A as well as to wheat germ lectin and this value was unchanged during hepatitis. In the serum of control rats, 90% of dipeptidyl aminopeptidase IV bound to concanavalin A but only 39% to wheat germ lectin.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:[Dipeptidyl aminopeptidase IV in hospitalized patients and in galactosamine hepatitis of the rat: Activity and lectin affinity chromatography in serum and hepatic plasma membranes]. 257 17

It is well established that caloric restriction extends life span and significantly retards the rate of occurrence of most age-associated degenerative disease processes. A paucity of data exists relative to the mechanisms by which caloric restriction accomplishes these events. We have examined the effect of caloric restriction in rats on several hepatic enzymes of intermediary metabolism. The activities of glycolytic and supporting enzymes including lactate dehydrogenase, pyruvate kinase, sorbitol dehydrogenase, and alcohol dehydrogenase were all decreased in response to caloric restriction. Fructose 1-phosphate aldolase and creatine phosphokinase were not altered. Likewise, enzymes associated with lipid metabolism (malic enzyme and glycerokinase) were reduced (fatty acid synthetase was reduced, but not to a statistically significant degree). Activities of enzymes supporting gluconeogenesis (glutamate oxaloacetate transaminase, tyrosine aminotransferase, glutamate pyruvate transaminase, glutamate dehydrogenase, amino acid oxidase, malate dehydrogenase, and glucose 6-phosphatase) were either unchanged or increased significantly by caloric restriction. Glucagon levels were decreased. Comparisons between young ad libitum fed and older calorically restricted rats revealed similar but not identical metabolic activity. These results suggest that caloric restriction produces an effect on intermediary metabolism, favoring the role of glucagon and glucose synthesis; but limiting the role of insulin and glucose catabolism in the liver. The former observation provides for the efficient support of peripheral tissues and the latter a level of energy production necessary only for self maintenance. Limited lipid metabolism suggests decreased potential for fatty acid epoxide formation and free radical damage to cellular macromolecules. Additionally, caloric restriction may delay the progressive age associated changes in the activities of some of the enzymes investigated.
...
PMID:Effect of chronic caloric restriction on hepatic enzymes of intermediary metabolism in the male Fischer 344 rat. 266 33


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---