Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.6.1.2 (alanine aminotransferase)
 26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

No interactions related to the analytical method were observed between chlorpromazine (1) or carbamazepine (2) and activities of alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), glutamate dehydrogenase (GLDH) or lactate dehydrogenase (LDH). With respect to its cytotoxic potential 1 in cultures of isolated rat hepatocytes increased markedly the release of enzymes into the culture medium, whereas the overall activities of the enzymes were not influenced. 2 in cultured hepatocytes caused no significant effects on the activities of the enzymes investigated. Besides the investigation of methodically related interactions in pooled human serum the methodic procedure including the use of cultures of isolated hepatocytes allows to study also pharmacologically and toxicologically related interactions between drugs and diagnostically relevant liver enzymes.
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PMID:[The effect of chlorpromazine and carbamazepine on diagnostically relevant liver enzymes]. 208 Feb 2

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.
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PMID:The role of iron and glutathione in t-butyl hydroperoxide-induced damage towards isolated perfused rat livers. 225 82

During an ultra-long-distance race (1000 km in 20 days) the influence of running was examined on the enzymes aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), gamma-glutamyl-transferase (GGT), and glutamate dehydrogenase (GLDH) with regard to their release from the liver cells or their induction. Furthermore the liver synthetic capacity was assayed by measuring the enzyme activity of cholinesterase and the concentration of serum albumin during the race. Of the 110 participants, 55 finished the race and only the results of these runners were used in our study. AP increased continuously from day 0 (mean = 102 U/L) to day 19 (mean = 120 U/L). A fivefold increase of AST and a twentyfold increase of CK up to day 3 was followed by a significant decrease towards the end of the race. ALT rose as well up to day 6 from a mean value of 8 U/L to 24 U/L but remained at this level. Surprising was the individual increase of the enzymes GLDH (up to twentyfold) and GGT (up to sixfold) in more than half of the finishers on various days indicating liver cell injuries. The activity of CHE and the concentration of serum albumin decreased during the race, both were significantly correlated.
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PMID:Ultra-long-distance running and the liver. 228 82

The activities of alanine-, aspartate- and branched-chain amino-acid transaminases, glutamine synthetase, glutamate dehydrogenase and adenylate deaminase in white adipose tissue of adult male rats have been determined in animals submitted to 12-h cold exposure (4 degrees C) or to 24-h food deprivation. Starvation resulted in small changes in glutamate dehydrogenase and alanine transaminase when expressed per unit of protein weight, inducing an increase in branched-chain amino-acid transaminase and glutamine synthetase. Cold exposure showed the same effects as starvation with respect to glutamate dehydrogenase and alanine transaminase, but induced increases in glutamine synthetase and aspartate transaminase. It is concluded that starvation increases the handling of some amino acids by white adipose tissue and the detoxification of the ammonia thus evolved. The changes observed suggest a different pattern of amino-acid metabolism enzyme changes with either cold or starvation.
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PMID:Amino-acid metabolism enzyme activities in rat white adipose tissue. 243 May 32

To contribute to our understanding of nitrogen metabolism in the developing chick we have studied in liver, intestine and yolk sac membrane the ontogeny of both aspartate- and alanine transaminases, glutamate dehydrogenase, adenylate deaminase, glutamine synthetase and xanthine dehydrogenase activities. Liver enzyme activities were much higher than those of the same enzymes in intestine and yolk sac membrane, the latter having the lowest activities. In the liver, both alanine transaminase and glutamate dehydrogenase increased their activity just before hatching, xanthine dehydrogenase and glutamine synthetase develop their highest activity just after hatching, while aspartate transaminase and adenylate deaminase attained the highest levels just with adulthood. From the pattern of enzyme activity in yolk sac membrane and intestine it can be inferred that after hatching, the amino-acid metabolism in these tissues is considerably enhanced, with higher production of ammonia from amino acids, as indicated by the rise in adenylate deaminase, as well as increased potentiality in production of both alanine and glutamine. It can be concluded that hatching coincides with a deep change of pace in amino-acid metabolism in the organs studied fully comparable with that observed in Mammals at the end of lactation, with the difference that the adaptation to the new diet in the case of the chick is much more sudden than weaning is for the rat.
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PMID:Amino-acid metabolism enzyme activities in the liver, intestine and yolk sac membrane of developing domestic fowl. 243 52

1. The objective of the present experiment was to study the effects of oak (Quercus incana) leaves rich in tannins on various enzyme activities of the bovine rumen. 2. The procedure employed was incubation of tannin-rich, very-low-tannin or virtually tannin-free leaves in nylon-gauze bags in the rumen, and determination of enzyme activities in microbes tightly bound to the solid matrix and in microbes loosely plus tightly attached to the solid matrix. 3. The activities of urease (EC 3.5.1.5), carboxymethylcellulose, glutamate dehydrogenase (EC 1.4.1.2) and alanine aminotransferase (glutamic-pyruvic transaminase) (EC 2.6.1.2) were significantly lower in the tannin-rich group, whereas the activities of glutamate ammonia ligase (glutamine synthetase) (EC 6.3.1.2; both gamma-glutamyltransferase (EC 2.3.2.2) and the forward reaction) were higher in the tannin-rich group. These changes were more marked in micro-organisms tightly bound to the solid matrix than in the more complex microbial compartment. 4. The protein, DNA and RNA contents, and protein: RNA ratio, were significantly lower in the tannin-rich group, whereas no difference was observed for protein: DNA between the groups. 5. Effects of tannin-containing extracts of oak leaves on various rumen enzymes in vitro showed a trend similar to that observed in nylon-gauze bags, suggesting that the changes observed in various compartments were due to the tannins of oak leaves.
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PMID:Effect of tannin-rich leaves of oak (Quercus incana) on various microbial enzyme activities of the bovine rumen. 246 31

A new spectrophotometric procedure is described for determining glutamate-dependent activities of aspartate aminotransferase, alanine aminotransferase, and ornithine aminotransferase with NADPH-linked glutamate dehydrogenase (GDH) from nitrate-grown Stichococcus bacillaris. The algal NADPH-GDH is highly specific for oxoglutarate and can catalyze the reduction of this keto acid in the presence of high glutamate concentrations, and thus is suitable for the measurement of oxoglutarate produced in glutamate-dependent amino-transferase reactions. The alga produces large amounts of NADPH-GDH which can be adequately purified in a few simple steps. The purified enzyme can be stored at 4 degrees C for several weeks without any detectable loss of activity. The algal NADPH-GDH can also be used for the estimation of small amounts of oxoglutarate in aqueous extracts.
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PMID:A spectrophotometric procedure for measuring oxoglutarate and determining aminotransferase activities using nicotinamide adenine dinucleotide phosphate-linked glutamate dehydrogenase from algae. 255 50

Hepatocytes were aseptically isolated from either the periportal (pp; zone 1) or the perivenous (pv; zone 3) region by digitonin-collagenase perfusion and cultured on type I collagen for 4 to 9 days. In freshly isolated cells the pp:pv activity ratios of the acinar marker enzymes gamma-glutamyltranspeptidase (gamma-GT), alanine aminotransferase (ALAT) and glutamate dehydrogenase (GLDH) were 2.8, 1.6 and 0.76, respectively. During culture ALAT and GLDH activities gradually declined, but the pp-pv difference was retained for at least 4 days. In contrast, the difference in the gamma-GT activity was rapidly lost, due to its fast initial activation in pv cells. The initial 7-ethoxycoumarin O-deethylase (ECDE) activity was higher in pv cells; this difference was retained for several days of culture and was increased by induction in vitro with either phenobarbital (PB) or beta-naphthoflavone (beta NF). Although the basal UDP-glucuronyltransferase (UDPGT) activity with either p-nitrophenol (pNP) or hydroxybiphenyl (HBP) as substrate did not differ significantly, the in-vitro PB- or beta NF-induced activity was higher in pv cells. Both glucuronidation and sulfation of methylumbelliferone tended to be higher in pv cells. Glutathione S-transferase was initially significantly higher in pv cells and this difference was augmented after in vitro induction by PB or beta NF. After six days in culture all the observed pp-pv differences had disappeared. These results suggest that hepatocytes isolated from the perivenous region seem to maintain their initially higher capacity for phase I and phase II drug reactions during culture and also respond more strongly than periportal cells to in vitro induction.
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PMID:Drug metabolism by periportal and perivenous rat hepatocytes. Comparison of phase I and phase II reactions and their inducibility during culture. 256 12

The activities in serum of alkaline phosphatase, gamma-glutamyltransferase, glutamate dehydrogenase, glutamic pyruvic transaminase and cholinesterase were compared after complete biliary obstruction (CBO) and choledochocaval fistula (CCF) in the rat. CCF was used as a model of complete biliary retention without bile stasis and without increased pressure in the biliary tract. The increases in AP, GLDH and gamma-GT within 24-h post-op. show no difference between the two experimental groups. The conclusion is that the retention of biliary constituents alone is responsible for the increase in the levels of serum activity and that other conditions like bile stasis and increased pressure in the biliary tract do not play an important role in the pathogenesis of these alterations. The rise of GPT activity in CCF is of a lesser degree than in CBO.
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PMID:The serum activities of AP, gamma-GT, GLDH, GPT and CHE after complete biliary obstruction and choledochocaval fistula in the rat. 256 1

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)
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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


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