Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Target Concepts:
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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)
The activities of six enzymes associated with carbohydrate metabolism were measured both in carcinomas and in normal breast tissues. The following differences were observed. 1. The carcinoma showed higher enzyme activities than the normal mammary tissue. 2. The ratios of
glutamate dehydrogenase
, hydroxybutyrate dehydrogenase, glutathione reductase and catalase to lactate dehydrogenase were lower in carcinomas than in normal tissues. Similarly, the ratios of
glutamate dehydrogenase
, hydroxybutyrate dehydrogenase, glutathione reductase and catalase to glucose-6-phosphate dehydrogenase were also significantly lower in carcinomas. 3. There were no significant differences in enzyme activities between I and II stage of the disease and the metastatic tissues, however, there were significant differences between I and III stage. The significance of these findings is discussed in terms of the alterations in the balance between the metabolic pathways.
Acta Biochim
Pol
1992
PMID:Enzyme activities in human breast tumours. 148 90
Monospecific antisera against three
glutamate dehydrogenase
(
GDH
) subunits of lupin root nodules were obtained. The use of sensitive mixed rocket immunoelectrophoresis enabled detection of seven
GDH
forms at the early stage of nodule development, thus providing evidence for the earlier hypothesized (L. Ratajczak et al., 1986, Physiol. Plant., 67, 685-689) random association of subunits 2g and 2a to form the remaining five
GDH
forms. All seven forms were localized in mitochondria. Immunological similarity was found between form 1 and plastid
GDH
.
Acta Biochim
Pol
1989
PMID:Immunochemical comparison of the glutamate dehydrogenase isoenzymes in yellow lupin root nodules. 248 4
ATP and glutamine are the sources of endogenous ammonia in rat brain synaptosomes. The amount of endogenous ammonia formed from exogenous ATP is not sufficient to assure the maximum rate of aspartate and glutamate accumulation in the synaptosomes utilizing pyruvate + malate. Addition of exogenous NH4+ or depolarization of synaptosome plasma membranes with high K+ concentration led to a twofold increase in the rate of accumulation of these amino acids. This indicates that both exogenous and endogenous NH4+ is involved in the synthesis of aspartate and glutamate in nerve terminals. Accumulation of glutamate was stimulated by aminooxyacetate and inhibited by haloperidol which indicates that NH4+ is bound in the reaction catalysed by
glutamate dehydrogenase
. Endogenous oxaloacetate derived from pyruvate metabolism was the substrate for synthesis of aspartate. Additive inhibition of aspartate accumulation by fluorocitrate and (-) hydroxyacetate shows that, in addition to the tricarboxylic acid cycle, the reaction catalysed by ATP-citrate lyase serves in the synaptosomes as another source of oxaloacetate.
Acta Biochim
Pol
1986
PMID:Synthesis of glutamate and aspartate in rat brain synaptosomes. 288 15
The ammonia concentration and changes in the activity of ammonia metabolizing enzymes in the brain tissue during ischemia/reperfusion were investigated in rats. During ischemia (0.5 h) we found a statistically significant increase in brain ammonia concentration and a significant decrease in
glutamate dehydrogenase
activity. After 1 h of reperfusion, a further accumulation of ammonia concentration was observed. Furthermore, the brain glutamine syntethase and
glutamate dehydrogenase
were decreased, whereas the brain glutaminase activity was increased. The causes for the changed activities of some ammonia metabolizing enzymes in brain after ischemia/reperfusion have been discussed.
Mater Med
Pol
PMID:Accumulation of ammonia and changes in the activity of some ammonia metabolizing enzymes during brain ischemia/reperfusion injury in rats. 780 37
In isolated rabbit renal kidney-cortex tubules 2 mM glycerol, which is a poor gluconeogenic substrate, does not induce glucose formation in the presence of alanine, while it activates gluconeogenesis on substitution of alanine by aspartate, glutamate or proline. The addition of either 5 mM 3-hydroxybutyrate or 5 mM acetoacetate to renal tubules incubated with alanine + glycerol causes a marked induction of glucose production associated with inhibition of glutamine synthesis. In contrast, the rate of the latter process is not altered by ketones in the presence of glycerol and either aspartate, glutamine or proline despite the stimulation of glucose formation. Acceleration of gluconeogenesis by ketone bodies in the presence of amino acids and glycerol is probably due to (i) stimulation of pyruvate carboxylase activity, (ii) activation of malate-aspartate shuttle as concluded from elevated intracellular levels of malate, aspartate and glutamate, as well as (iii) diminished supply of ammonium for glutamine synthesis from alanine resulting from a decrease in
glutamate dehydrogenase
activity.
Acta Biochim
Pol
1997
PMID:Ketone bodies activate gluconeogenesis in isolated rabbit renal cortical tubules incubated in the presence of amino acids and glycerol. 936 Jul 22
The effect of 2-aminobicyclo[2.2.1]heptan-2-carboxylic acid (BCH), an L-leucine nonmetabolizable analogue and an allosteric activator of
glutamate dehydrogenase
, on glucose and glutamine synthesis was studied in rabbit renal tubules incubated with alanine, aspartate or proline in the presence of glycerol and octanoate, i.e. under conditions of efficient glucose formation. With alanine+glycerol+octanoate the addition of BCH resulted in a stimulation of alanine and glycerol consumption, accompanied by an increased glucose, lactate and glutamine synthesis. In contrast, when alanine was substituted by either aspartate or proline, BCH altered neither glucose formation nor glutamine and glutamate synthesis, while an accelerated glycerol utilization was accompanied by a small increase in lactate production. In view of the BCH-induced changes in intracellular metabolite levels the acceleration of gluconeogenesis by BCH in the presence of alanine+glycerol+octanoate is probably due to (i) increased uptake of alanine via alanine aminotransferase, (ii) stimulation of phosphoenolpyruvate carboxykinase, a key-enzyme of gluconeogenesis, (iii) rise of glucose-6-phosphatase activity, as well as (iv) activation of the malate-aspartate shuttle resulting in an augmented glycerol utilization for lactate and glucose synthesis.
Acta Biochim
Pol
1998
PMID:Importance of glutamate dehydrogenase stimulation for glucose and glutamine synthesis in rabbit renal tubules incubated with various amino acids. 991 11
One of the hypotheses in amyotrophic lateral sclerosis (ALS) indicates on excitatory amino acids as the cause of neuronal death. Changes in their concentration in the tissues and body fluids may be the consequence of a defect in their transport, as well as abnormal activities of glutamate metabolizing enzymes. Abnormal synthesis/degradation of these enzymes and/or influence of activators/inhibitors should be taken into account. The activity of enzymes of glutamate metabolism of rat spinal cord in vitro in the presence of serum and cerebrospinal fluid (CSF) of 20 patients with ALS and 20 healthy controls was tested. In the presence of serum of the ALS patients glutaminase was significantly stimulated, instead of being inhibited; the inhibition of GABA aminotransferase, glutamate decaboxylase and aspartate aminotransferase was less evident than in the controls,
glutamate dehydrogenase
lost its activity more than in control conditions, the inhibition of glutamine synthetase was comparable to that when normal serum was applied. The activity of the enzymes in the presence of CSF of ALS patients was generally similar to that of normal CSF, except of glutaminase which was stimulated and GABA aminotransferase, which was inhibited stronger than in the presence of normal CSF. This study indicates, that changes in glutamate concentration in tissues and body fluids in ALS may be caused, at least partly, by abnormalities in the activity of glutamate metabolism enzymes, which are in turn induced by neurotoxic agents present in body fluids of ALS patients.
Neurol Neurochir
Pol
2001
PMID:[Neurotoxic activity of serum and cerebrospinal fluid of amyotrophic lateral sclerosis patients against some enzymes of glutamate metabolism]. 1173 83