Glutamine and hyperammonemic crises in patients with urea cycle disorders.

 lost predictive significance (OR=1.47; p=0.439) when concomitant 

 was taken into account, whereas the predictive value of baseline ammonia ≥ 1.0 upper limit of normal (ULN) was highly statistically significant (OR=4.96; p=0.013).

Glycine and hyperammonemia: potential target for the treatment of hepatic encephalopathy

Ornithine phenylacetate revisited

 levels is due to the stimulation of ammonia removal in the form of 

 (through glutamine synthetase), the direct excretion of ammonia in the form phenylacetylglutamine and to a normalisation of glutaminase activity in the gut.

Reduced glutamine concentration improves protein production in growth-arrested CHO-DG44 and HEK-293E cells

 consumption results in the production of 

Acute hyperammonemia activates branched-chain amino acid catabolism and decreases their extracellular concentrations: different sensitivity of red and white muscle

Glutamine as a mediator of ammonia neurotoxicity: A critical appraisal.

Recent studies have demonstrated a "Trojan Horse"-like effect of Gln in microglia, as well as an interference by

 with the activation of the NMDA/NO/cGMP pathway by 

 as measured in whole brain, a process that likely also involves neurons.

New frontiers in gut nutrient sensor research: prophylactic effect of glutamine against Helicobacter pylori-induced gastric diseases in Mongolian gerbils.

 decreased chemokine production and cell death through inhibition of cellular accumulation of 

, resulting in the prevention of H. pylori-induced gastric diseases in vivo.

The anaplerotic flux and ammonia detoxification in hepatic encephalopathy

, whereby anaplerotic mechanisms in the astrocytes have to be sufficient to replenish Krebs cycle intermediates.

The molecular pathogenesis of hepatic encephalopathy.

 within astrocytes, causing an osmotic imbalance resulting in cell swelling and ultimately brain oedema.

Relation between glutamine, branched-chain amino acids, and protein metabolism.

Decreased protein breakdown also was observed when

Alterations in expression of genes coding for key astrocytic proteins in acute liver failure

 may cause cell swelling via the osmotic effects of an increase in astrocytic 

 concentrations or by inhibition of glutamate removal from brain extracellular space.

Metabolism of branched-chain amino acids and ammonia during exercise: clues from McArdle's disease.

 (in mumol/min) has been estimated to be five- to tenfold larger in one of these patients than in healthy individuals exercising at comparable relative work load.

The ability to utilise ammonia as nitrogen source is cell type specific and intricately linked to GDH, AMPK and mTORC1

 promoted a rapid and transient activation of AMPK, whereas, additional 

 supplementation blocked this starvation-induced AMPK activation.

Minimal hepatic encephalopathy in children with chronic liver disease: Prevalence, pathogenesis and magnetic resonance-based diagnosis.

 had a significant positive correlation with 

, IL-6, TNF-α and MD of various brain regions.

Evidence of a vicious cycle in glutamine synthesis and breakdown in pathogenesis of hepatic encephalopathy–therapeutic perspectives

As only one molecule of ammonia is detoxified in GLN synthesis whereas two molecules may … in GLN breakdown, these events can be seen as a vicious cycle in which enhanced

 leading to its subsequent catabolism and increase in ammonia levels in the blood.

Oral glutamine challenge improves the performance of psychometric tests for the diagnosis of minimal hepatic encephalopathy in patients with liver cirrhosis.

 in cirrhosis leading to secondary cognitive impairment.

Impact of oxygen supply on rtPA expression in Escherichia coli BL21 (DE3): ammonia effects

 had no significant impact on cell growth and oxygen respiratory activity but significantly depressed the activities of 

 synthetase/glutamate synthase and glutamate dehydrogenase, suggesting that ammonium ion as a nitrogen source improved the protein expression by mediating ammonia-assimilating enzymes.

Management of hepatic encephalopathy in patients with cirrhosis.

Plasma glutamine and ammonia concentrations in ornithine carbamoyltransferase deficiency and citrullinaemia

The relationship between the plasma concentrations of

 is not a simple linear one and there are significant differences between the two disorders.

Effects of high-volume plasmapheresis on ammonia, urea, and amino acids in patients with acute liver failure

OBJECTIVE:In acute liver failure (ALF), urea production is severely impaired, and detoxification of

 synthesis plays an important protective role.

Effect of sodium benzoate on blood ammonia response to oral glutamine challenge in cirrhotic patients: a note of caution

 load both before (from 66 ± 12 μg/dl to 123 ± 34 μg/dl and 179 ± 53 μg/dl after 30 and 60 min, … ± 27 μg/dl to 185 ± 49 μg/dl and 250 ± 39 μg/dl after 30 and 60 min, respectively; ANOVA p= 0.00001).

Oral glutamine challenge in cirrhotics pre‐ and post‐liver transplantation: A psychometric and analyzed EEG study

 from a mean fasting value ranging between 58 µmol/L to 120 µmol/L (P < .01), between significant prolongation of reaction times … 428 ms (P < .01), and an increase in mean EEG amplitude between 68.5 µV to 78.6 µV (P < .001).

Renal ammoniagenesis in humans with chronic potassium depletion.

 was significantly increased (56.6 +/- 5.9 mumol/min.1.73 m2 vs. 34.6 +/- 3.1 in controls), and this could account for 

Effects of somatostatin on plasma ammonia and amino acid profile during fasting and after protein feeding in cirrhotic patients.

 concentrations were inversely correlated (r = -80; p less than 0.001) After protein ingestion, somatostatin slowed the maximal plasma increase in ammonia and alpha-… h plasma response was not reduced, and even, in some instances, significantly increased (valine, leucine, glutamine, alanine and serine) with respect to saline.

[Direct phenol-hypochlorite method for determining glutaminase activity].

Conditions are selected for detecting enzymatically formed

 in the presence of such a high-labile substrate as 

Glucose Metabolism, Lactate, and Ammonia Production by the Human Placenta In Vitro

 (1 and 2 μmoles/ml) produced a significant increase in 

 production over that found in the controls, but no change in glucose utilization.

Inhibitory effect of glutamine and ammonia on replication of influenza virus in ascites tumor cells.

There appears to be a relation between the formation of

 and the observed inhibitory effects of this substance.

Effects of acute ammonia exposure on antioxidant and detoxification metabolism in clam Cyclina sinensis.

 content in T1 and T2 increased significantly from 6 h to 24 h after exposed to 

 and they were significantly higher than those in the control.

Metabolic changes and stress damage induced by ammonia exposure in juvenile Eriocheir sinensis.

The detoxification of ammonia into urea and

Nutrition and metabolism of glutamate and glutamine in fish

 to farmed fish can improve their growth performance, intestinal development, innate and adaptive immune responses, skeletal muscle development and fillet quality, 

The razor clam Sinonovacula constricta uses the strategy of conversion of toxic ammonia to glutamine in response to high environmental ammonia exposure.

 resulted in a significant increase of glutamate concentration and 

13 C Flux Analysis Reveals that Rebalancing Medium Amino Acid Composition can Reduce Ammonia Production while Preserving Central Carbon Metabolism of CHO Cell Cultures.

 was reduced by manipulating the amino acid composition of the culture medium; specifically, 

, glutamate, asparagine, aspartate, and serine levels were adjusted.

Ornithine phenylacetate prevents disturbances of motor-evoked potentials induced by intestinal blood in rats with portacaval anastomosis.

This is probably due to the enhancement of

 synthesis and metabolism, which results in a lower rise of 

 and the prevention of changes in glutamate in microdialysate.

Detoxification of Ammonia in Mouse Cortical GABAergic Cell Cultures Increases Neuronal Oxidative Metabolism and Reveals an Emerging Role for Release of Glucose-Derived Alanine

Collectively, our results demonstrate that (1) formation of

; (2) neuronal oxidative metabolism is increased in the presence of ammonia; and (3) synthesis and release of alanine is likely to be important for ammonia detoxification as a supplement to formation of glutamine.

Inhibition of glutamine synthetase during ammonia exposure in rainbow trout indicates a high reserve capacity to prevent brain ammonia toxicity

Glutamine inhibits ammonia-induced accumulation of cGMP in rat striatum limiting arginine supply for NO synthesis

 applied in vivo (via microdialysis) or in vitro (to rat brain cortical slices) reduced NO and cGMP accumulation in the presence and/or absence of 

, but not cGMP synthesis induced by the NO donor sodium nitroprusside.

Effect of ammonia, glutamine, and serum on calcineurin, p38MAPK-diP, GADD153/CHOP10, and CNTF in primary rat astrocyte cultures

GADD153/CHOP10 content was always higher under hyperammonemic conditions as well as under glutamine exposure, probably due to the osmotic stress provoked by

 accumulation, which was induced after exposure to 

Effect of Glutamine Synthesis Inhibition with Methionine Sulfoximine on the Nitric Oxide–Cyclic GMP Pathway in the Rat Striatum Treated Acutely with Ammonia: A Microdialysis Study

The results of the present study suggest that

, at physiological concentrations, may ameliorate excessive activation of the NO–cGMP pathway by neurotoxic concentrations of 

Regional amino acid neurotransmitter changes in brains of spf/Y mice with congenital ornithine transcarbamylase deficiency

 was observed, consistent with the exposure of these brains to increased concentrations of 

Ammonia-Induced Extracellular Accumulation of Taurine in the Rat Striatum In Vivo: Role of Ionotropic Glutamate Receptors

 accumulation somewhat less than Tau accumulation.

Glutamine‐induced free radical production in cultured astrocytes

While the synthesis of glutamine has generally been viewed as the principal means of ammonia detoxification, this presumed beneficial effect has been questioned as growing evidence suggest that some of the deleterious effects of

Excitotoxic mechanism of cell swelling in rat cerebral cortical slices treated acutely with ammonia

, an amino acid whose excess accumulation has been implicated in hyperammonemic oedema.

Glucose alleviates ammonia-induced inhibition of short-chain fatty acid metabolism in rat colonic epithelial cells.

 decreased metabolism by rat colonic epithelial cells of butyrate and acetate to CO2 and ketones but increased oxidation of glucose and 

Role of glutamine and arginase in protection against ammonia-induced cell death in gastric epithelial cells.

 also inhibits the uptake and facilitates the extrusion of 

The effect of sub-lethal ammonia exposure on fed and unfed rainbow trout: the role of glutamine in regulation of ammonia.

Activity of glutamine synthetase in brain and liver was increased corresponding to an increase in

 concentrations when fish were exposed to 

[Effects of ammonia on cell metabolism in the culture of recombinant CHO cells].

It was showed that the yields of cells to glucose,

 and other consumed amino acids decreased with the increase of initial 

Ammonia Removal Using Hepatoma Cells in Mammalian Cell Cultures

 was higher in the absence than in the presence of 

Functional ureogenesis in the gobiid fish Mugilogobius abei.

 contents and glutamine synthetase activities in the liver and muscle increased greatly following exposure to 

Effects of vascular or luminal administration and of simultaneous glucose availability on glutamine utilization by isolated rat small intestine

Glutamine consumption (–110±6 vs. –70±5 or –91±5 vs. –73±7 nmol min–1 g–1; ….8±0.5 vs. 7.8±0.4 nmol min–1 g–1; P<0.05 each) or

 (124±7 vs. 88±4; P<…) became available in addition to 

Inhibitory effect of valproate on weak organic acid uptake in rat renal proximal tubules.

 production by the tubules, with the glutamine-induced ammoniagenesis being further augmented by VPA, while glutamate failed to affect the basal ammoniagenesis.

Model Simulation and Analysis of Perfusion Culture of Mammalian Cells at High Cell Density

 concentration can also be reduced to a certain extent without significantly impairing the growth and antibody production but considerably reducing the 

Multinuclear NMR Spectroscopy Studies on NH4Cl-Induced Metabolic Alterations and Detoxification Processes in Primary Astrocytes and Glioma Cells

 (3 h incubation with NH4Cl) raised the concentration of 

 and other amino acids, such as glutamate and aspartate, and decreased myo-inositol, hypotaurine, and taurine concentrations.

Ammonia stimulates glutamine uptake to the cerebral non-synaptic mitochondria of the rat

 increased Vmax of the saturable component of 

 uptake by > 20%, without affecting K(m), but did not change a non-saturable component of GLN transport representing diffusion or uptake mediated by a very low affinity carrier.

Decreased ureagenesis from alanine, but not from ammonia and glutamine, in the perfused rat liver after partial hepatectomy

 (0.5 mmol/L) was accelerated approximately 10‐fold, and the significant difference in the rate of urea formation between HX and SO rats was abolished.

Urea synthesis in enterocytes of developing pigs.

This hitherto unrecognized urea synthesis in these cells may be a first line of defence against the potential toxicity of

 produced by the extensive intestinal degradation of 

 (a major fuel for enterocytes) and derived from diet and luminal micro-organisms.

The intensity of acidosis differentially alters the pathways of ammoniagenesis in LLC-PK1 cells.

 resulted in a substantially lower amounts of 15N 

Chronic hyperammonemia prevents changes in brain energy and ammonia metabolites induced by acute ammonium intoxication.

 increased 12.8-fold while glutamate and aspartate decreased by approximately 40% and 

 and alanine raised by 37% and 93%, respectively; in hyperammonemic rats ammonia increased 6.9-fold while glutamate, glutamine and alanine were not significantly affected.

Regulation of orotic acid biosynthesis and excretion induced by oral glutamine administration in mice.

 at doses of 2.5 to 4.0 mmol/100 g of body wt caused a significant increase in 

Physiological Levels of Ammonia Regulate Glutamine Synthesis from Extracellular Glutamate in Astrocyte Cultures

 synthesis was increased from 3.6 to 9.3 nmol/mg of protein/min by addition of 100 μM 

, and intracellular glutamate was reduced from 262 to 86 nmol/mg of protein after 30 min.

Effects of sublethal concentrations of phosphamidon, methyl parathion, DDT, and lindane on tissue nitrogen metabolism in the penaeid prawn, Metapenaeus monoceros (Fabricius).

Effects of Acute Hyperammonemia on Cerebral Amino Acid Metabolism and pHi In Vivo, Measured by 1H and 31P Nuclear Magnetic Resonance

The results reported here support earlier findings that an increased

 concentration has a pronounced effect on the brain concentrations of two important amino acids, glutamate and 

Ammonia production from intraluminal amino acids in canine jejunum.

 significantly (P less than 0.01) increased 

 into mesenteric venous blood by 37, 42, and 106%, respectively, whereas threonine, serine, and glycine had no effect.

[Subcellular localization of glutamine synthetase activity in carp muscle tissue and liver].

Comparison of the obtained results with data from literature testifies to a coincidence of the subcellular localization of the processes of

, thus confirming a view of the leading role of glutaminesynthetase in ammonia detoxication in carps.

Incorporation of intraportal ammonia-N into blood and tissue nitrogenous compounds in chickens fed low and high protein diets.

 which was increased during 6 hr infusion of 

 was derived from infused ammonia-N and the remainder from endogenous nitrogen, irrespective of protein intake.

Some metabolic effects of ammonia on astrocytes and neurons in primary cultures.

In astrocytes, glutamate levels tended to decrease and

 levels tended to increase following acute exposure to 

; in neurons, both glutamine and glutamate levels decreased.

Gamma glutamyltransferase ammonia production from glutamine: effect of physiological glutathione concentration.

 was 1.6 mM some 2 fold greater than the actual plasma concentration.

Nitrogen sources for renal ammoniagenesis: study with 15N amino acid.

Studies with tubules incubated in Krebs medium alone indicated that, in both control and acidosis, the calculated fraction of

 derived from endogenous sources was significantly decreased by addition of either 0.7 or 2.5 mM 

Renal tissue metabolism in the rat during chronic metabolic alkalosis: importance of glycolysis.

 fell by 40% with a decrease in the activity of glutaminase I and glutamate dehydrogenase.

Glutamine synthesis in the perfused rat kidney and in isolated rat cortical tubules: regulation by pH.

 production in isolated cortical tubules.

Hepatocyte heterogeneity in ammonia metabolism: impairment of glutamine synthesis in CCl4 induced liver cell necrosis with no effect on urea synthesis.

, whereas urea synthesis was not affected by CCl4 pretreatment.

Evidence of activation of the renal glutamate dehydrogenase pathway in intact acidotic dogs.

 into chronically acidotic, normal and acutely alkalotic dogs enhanced 

 production; more was formed as glutamine loading increased.

Mechanism by which enhanced ammonia production reduces urinary potassium excretion.

Free amino acids in fish brain: normal levels and changes upon exposure to high ammonia concentrations in vivo, and upon incubation of brain slices.

When fish (Carassius auratus) were kept in water containing controlled concentrations of

 increased up to ten times, that of several other amino acids increased to a lesser extent.

Renal hemodynamics and ammoniagenesis. Characteristics of the antiluminal site for glutamine extraction.

Systemic venous or renal intra-arterial infusion of

 during arterial constriction increased renal production of 

Role of ammonia as a buffer in the central nervous system.

 initially rose but later declined as changes in the CNS concentration of 

 and glutamic acid indicated activation of this pathway of ammonia detoxification.

Metabolism of glutamine and glutamate by rat liver mitochondria.

The 'neurotoxicity' of L-2,4-diaminobutyric acid.

 of blood and brain slightly and the concentration of 

A glutamine-dependent enzyme for the synthesis of carbamyl phosphate for pyrimidine biosynthesis in fetal rat liver.

 analogues inhibit the ability of either glutamine or 

Initial steps in pyrimidine synthesis in Ehrlich ascites carcinoma in vitro. II. The synthesis of carbamyl phosphate by a soluble, glutamine-dependent carbamyl phosphate synthetase.

The Km for glutamine is close to 10-5 m, whereas the Km for ammonium chloride is about 5 x 10-3 m. The incorporation is inhibited by

QUANTITATIVE ASPECTS OF CO2 FIXATION IN MAMMALIAN BRAIN IN VIVO *

The rate of CO2 fixation is increased when the tissue is exposed to a metabolic stress, such as an elevated

 concentration, which results in an increased synthesis of 

CHANGES IN THE AMMONIA AND GLUTAMINE CONTENT OF THE RATBRAIN INDUCED BY ELECTRIC SHOCK

Ammonium salts may be of special importance in view of their activity as cerebral irritants, and

 in the brain (ELLIOTT, 1951 ; WEIL-MALHERBE, 1950).

An in vitro study of urea and ammonia production and transport by the intestinal tract of fed and fasted rainbow trout: responses to luminal glutamine and ammonia loading

supp.ai

Discover Supplement-Drug Interactions

Possible Interaction: Ammonia and Glutamine

Share:

Ammonia

Glutamine

Research Papers that Mention the Interaction