Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.1.1.49 (glucose-6-phosphate dehydrogenase)
 7,794 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bioluminescent methods are widely used for the assay of the co-factors, NADH and ATP. Although the bioluminescent method is highly sensitive, the enzymes used are unstable and expensive. Therefore a chemiluminescent method would be valuable in clinical routine assay. We have developed a chemiluminescent method for the assay of NADH using the 1-methoxy-5-methylphenazinium methyl sulphate (1-MPMS)/isoluminol(IL)/microperoxidase(m-POD) system. In order to increase the sensitivity of this method, enzymatic cycling system was coupled to the chemiluminescent assay of NADH. Alcohol dehydrogenase and malate dehydrogenase were used as the cycling enzyme. The standard curve was obtained in the range from 3 X 10(-14) to 5 X 10(-12) mol/assay. The detection limit of NADH was 30 fmol/assay which was comparable to that of the bioluminescent method using bacterial luciferase. Two chemiluminescent methods for the assay of ATP have been developed. Method 1 is the system using hexokinase/G6PDH and 1-PMS/IL/m-POD, and method 2 is the system based on the enzymatic cycling reaction of ATP using hexokinase/pyruvate kinase. Method 2 is 1000/fold more sensitive than the method 1. The detection limit of ATP was 10 fmol/assay.
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PMID:Chemiluminescent assay of co-factors. 280 Dec 32

The histochemical activities of nonspecific acid and alkaline phosphatases, NADH- and NADPH-tetrazolium reductases, alpha-glycerophosphate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase, lactate dehydrogenase and glucose-6-phosphate dehydrogenase were investigated in kidneys from rats treated with lithium and lithium plus neuroleptics. During the first 8 weeks of lithium treatment the activity of NADH-tetrazolium reductase, succinate dehydrogenase and alpha-glycerophosphate dehydrogenase activity in the collecting ducts increased. The other enzymes did not change. After 8 weeks of treatment no further changes in enzyme activity occurred. Withdrawal of lithium caused normalization of enzyme activity after 8 weeks. A decrease in concentration ability was found in parallel with the increase in enzyme activities (p less than 0.001). The changes in enzyme activity were not significantly correlated to morphological changes in the collecting ducts. Treatment with neuroleptics alone caused no change in enzyme activity. During combined lithium plus neuroleptic treatment the enzyme activities changed in a similar way as during lithium therapy, but the changes were less pronounced. In parallel, a less pronounced decrease in concentration ability was found during this treatment.
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PMID:Correlation between distal nephron enzyme activity, structure and function in rats during lithium and lithium plus neuroleptic treatment. 285 95

A reexamination of the question of specificity of reinnervation of fast and slow muscle was undertaken using the original "self" nerve supply to the fast lateral gastrocnemius (LG) and slow soleus muscles in the rat hindlimb. This paradigm takes advantage of the unusual situation of a common nerve branch, which supplies both a fast and slow muscle, and of the opportunity to keep the reinnervating nerve in its normal position. In addition it provides a test of the effects of cross-reinnervation among muscles of the same functional group. The properties of soleus and LG muscles and of individual muscle units were characterized in normal rats and in rats 4-14 mo after cutting the lateral gastrocnemius-soleus (LGS) nerve and suture of the proximal stump to the dorsal surface of the LG muscle. Individual muscle units were functionally isolated by stimulation of single motor axons to LG or soleus muscle contained in teased filaments in the L4 and L5 ventral roots. Motor units were classified as fast contracting fatiguable (FF), fast contracting fatigue resistant (FR), and slow (S) on the basis of criteria described in the cat by Burke et al. and applied to rat muscle units by Gillespie et al. Muscle fibers were classified as fast glycolytic (FG), fast oxidative glycolytic (FOG), and slow oxidative (SO) on the basis of histochemical staining for myosin ATPase, nicotinamide-adenine dinucleotide diaphorase (NADH-D), and alpha-glycerophosphate (alpha-GPD). Reinnervated muscles developed less force and weighed less in accordance with having fewer than normal motor units and having lost denervated muscle fibers. Normal LG contained a small proportion of S-type motor units (9%), whereas the majority (80%) of control soleus units were S type. After reinnervation, each muscle contained similar proportions of fast and slow motor units with S-type units constituting 30% of units in both muscles. When compared with the normal motor-unit sample, there was no significant change in average twitch and tetanic force in reinnervated muscles for each type of motor unit. However, the range within each type was greater, and there was considerable overlap between types. Twitch contraction time was inversely correlated with force in normal and reinnervated muscles as shown previously in self- and cross-reinnervated LGS in the cat. Changes in proportions of motor units in reinnervated LG were accompanied by corresponding changes in histochemical muscle types. This contrasted with reinnervated soleus in which the proportion of muscle fiber types was not significantly changed from normal despite significant change in motor-unit proportions.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Motor units and histochemistry in rat lateral gastrocnemius and soleus muscles: evidence for dissociation of physiological and histochemical properties after reinnervation. 295 72

Reduced glutathione, enzymes involved in its metabolism and other cytosolic activities were evaluated in liver preparations of Wistar rats fed with a diet supplemented with 2-acetylaminofluorene (0.05%) and/or with glutathione or N-acetyl-L-cysteine (0.1%). The treatment lasted 4 cycles, each composed of 3 weeks of special diet followed by 1 week of standard diet. The carcinogen produced a considerable increase in gamma-glutamyl transpeptidase in liver homogenates at cycles III and IV, with an irreversible trend which was not discontinued even during the weeks of standard diet. Moreover, generally from cycle I, 2-acetylaminofluorene stimulated several enzyme activities in the liver cytosol, such as glutathione S-transferase, glutathione reductase, glucose 6-phosphate dehydrogenase, NADH- and NADPH-dependent diaphorases. Administration of the two aminothiols to untreated rats resulted in a significant enhancement of glutathione peroxidase, glucose 6-phosphate dehydrogenase and diaphorases. In 2-acetylaminofluorene-treated rats, both thiols further stimulated glutathione S-transferase during the last treatment cycles and attenuated gamma-glutamyl transpeptidase activity, which however was not sufficient to thoroughly counteract the liver lesions due to the massive feeding of the carcinogen. Hepatocellular glutathione was enhanced during the last cycle of treatment with 2-acetylaminofluorene, and was further increased by co-administration of exogenous glutathione.
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PMID:Effects of aminothiols in 2-acetylaminofluorene-treated rats. II. Glutathione cycle and liver cytosolic activities. 297 75

Hepatocytes were prepared from 15 degrees C acclimated catfish (Ictalurus punctatus) and maintained in primary culture for 20 days on biomatrix at 7, 15, and 25 degrees C without hormones or serum to determine if cells can directly adapt to temperature. Specific activities of cytochrome-c oxidase, NADH-cytochrome c reductase, citrate synthase, and glucose-6-phosphate dehydrogenase showed acclimatory rate compensation (7 greater than 15 greater than 25 degrees C cultured); 6-phosphogluconate dehydrogenase had activity changes of 15 greater than 7 greater than 25 degrees C cultured; activity of lactate dehydrogenase occurred in the series 7 greater than 15 = 25 degrees C. Protein synthesis of freshly isolated hepatocytes from catfish acclimated to the three temperatures exhibited acclimatory rate compensation. In contrast, protein synthesis of cultured hepatocytes occurred in the series 15 greater than 25 greater than 7 degrees C cultured. Protein degradation was highest at 25 degrees C followed by cells at 15 and 7 degrees C. Cultured hepatocytes showed incomplete temperature acclimation in vitro by way of enzyme activity changes and of protein synthesis. This suggests that some factor(s), such as hormones, is probably necessary to mediate the full temperature-acclimation process.
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PMID:Can cultured teleost hepatocytes show temperature acclimation? 300 35

Within the uterine glands, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the activities of G-6-PDH, 6-PGDH, and cytochrome oxidase increase within secreting cells during the 2nd half of pregnancy. The activities of the other enzymes remained almost unchanged during the period of investigation. The description of our results distinguishes between gland neck, middle, and distal part of the secretory unit, respectively. In general, the enzyme activities are similar within the middle and distal gland segments, but lower in the epithelia of the neck region. The activity of dehydrogenases was medium to intensive within the middle and distal gland segments, but only low to medium within the neck portion. Of the hydrolases, the acid phosphatase, ATPase, leucine aminopeptidase, and beta-galactosidase demonstrated an intensive activity within activity secreting cells. The enzyme activities of the gland epithelia are compared with these of the uterine surface epithelia and the histochemical results are discussed in context with their significance in histiotrophic nutrition.
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PMID:[Enzyme histochemistry of the pig placenta. III. Histotopics of enzymes in the uterine epithelium]. 309 49

The levels of ATP, ADP, AMP, NADP, NADPH, NAD, NADH and reduced glutathione were determined in the red blood cells of individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, beta-thalassemia (beta-thal) heterozygotes and in a boy carrying both mutations. The results obtained confirmed a reduced concentration of NADPH in G6PD deficiency and showed that with the combination of both diseases, the red blood cell contained practically undetectable levels of NADPH. Assays of some red blood cell enzyme activities known to be markedly influenced by cell age suggested that a younger mean red cell population is present in beta-thal/G6PD deficiency. Thus, the marked oxidative stress caused by beta-thal, that is apparently incompatible with G6PD deficiency, in fact exists, probably because of the residual activity of this enzyme in the younger red cells.
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PMID:Redox and energetic state of red blood cells in G6PD deficiency, heterozygous beta-thalassemia and the combination of both. 309 52

The new calcium antagonist anipamil (1,7-bis-(3-methoxyphenyl)-3-methylaza-7-cyano-nonadecane) exhibited a pronounced protective effect against isoprenaline-induced myocardial necrosis in rats. Anipamil was administered in single doses of 10 or 20 mg/kg daily for 4 days. 30 mg/kg isoprenaline was given by subcutaneous injection on the 3rd and 4th days of the study. The protective effect of anipamil was assessed by histological investigations, and its effect on the activity of the enzymes succinate dehydrogenase, NADH-NBT reductase, acid phosphatase and glucose-6-phosphate dehydrogenase in experimentally-induced myocardial damage was assessed quantitatively by microphotometry. The protective effect of anipamil against isoprenaline-induced myocardial necrosis was definitely dose-dependent: 10 mg/kg anipamil exhibited a partial protective effect, whilst 20 mg/kg anipamil protected the heart completely.
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PMID:Protective effect of the new calcium antagonist anipamil against isoprenaline-induced cardionecrosis in rats. 313 Aug 38

Possible protective effects of Allium sativum and Crataegus--alone and in combination--on isoprenaline (isoproterenol)-induced heart, liver and pancreas damage were studied using rats as test animals. Pretreatment with Allium sativum alone, or in combination with Crataegus, resulted in protective effects on isoprenaline-induced damage of heart, liver, and pancreas. These effects proved to be dose-dependent. The following parameters were used to evaluate the protective effect: Clinical signs, qualitative histological and histoenzymatical findings, as well as quantitative microphotometric determination of enzymatic activities of succinate dehydrogenase, NADH-NBT reductase, acid phosphatase and glucose-6-phosphate dehydrogenase in cardiac, hepatic and pancreatic tissues. The underlying mechanisms are discussed. The results suggest that Allium sativum, resp. Allium sativum plus Crataegus exert a pronounced protective effect.
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PMID:The protective effect of Allium sativum and crataegus on isoprenaline-induced tissue necroses in rats. 321 41

Fundamental aspects of the reduction of tetrazolium salts were investigated and, in particular, the role of oxygen in the reduction. It was found that oxygen had a competitive inhibitory effect on the reduction of (Tetra)Nitro BT mediated by NADH and phenazine methosulphate. This competitive effect, under aerobic conditions, could be reversed by using tetrazolium concentrations of 5 mM. Oxygen did not have a significant effect on BPST reduction, whereas the inhibitory effect of oxygen on the reduction of Neotetrazolium was not reversed by increasing the tetrazolium concentration. The oxygen effect on Nitro BT reduction was considerably less when macromolecular substances such as albumin or polyvinyl alcohol were added to the medium. This may be due to increased Nitro BT concentrations being built up at the surface of macromolecules due to the nonpolar components of the Nitro BT molecule. When demonstrating glucose-6-phosphate dehydrogenase activity in vitro or in tissue sections with the use of Nitro BT, oxygen also had a direct inhibitory effect, even when azide was added to the medium for the inhibition of flavoprotein-mediated electron transfer to oxygen. Again, this direct inhibition of Nitro BT reduction by oxygen could be excluded by using a high Nitro BT concentration. Macromolecules present in the incubation medium or in tissue sections counteracted the oxygen effect. It is concluded that the maximum reaction rate and optimum localization of dehydrogenases is obtained when histochemical media are used containing 5 mM (Tetra)Nitro BT and 20% polyvinyl alcohol.
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PMID:On the role of oxygen in dehydrogenase reactions using tetrazolium salts. 322 Jul 95


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