Activities of Enzymes for Glucose Catabolism in the Swimbladder of the European Eel Anguilla Anguilla

1991 ◽  
Vol 156 (1) ◽  
pp. 207-213 ◽  
Author(s):  
BERND PELSTER ◽  
PETER SCHEID
Keyword(s):  
White Muscle ◽  
Anguilla Anguilla ◽  
Great Depth ◽  
Pentose Phosphate ◽  
European Eel ◽  
Glucose Catabolism ◽  
Rete Mirabile ◽  
Special Adaptation ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Pentose Phosphate Shunt

Gas secretion into the swimbladder of the eel relies on the production of CO2 and lactic acid from glucose in the swimbladder epithelium. The activities of the enzymes involved in glucose catabolism have been measured and compared with those in the rete mirabile, the liver and white skeletal muscle to evaluate whether the pentose phosphate shunt may contribute to glucose metabolism in the swimbladder tissue. The activities of enzymes of the pentose phosphate shunt were higher in the swimbladder epithelium than in white muscle, and close to those in the liver. The activities of the enzymes of anaerobic glycolysis were 2–5 times higher in the swimbladder epithelium than in the rete mirabile, reaching or even exceeding the levels in liver and white muscle, whereas the activities of the enzymes of oxidative metabolism were extremely low. Compared to enzymes of the other tissues, swimbladder phosphofructokinase and glucose-6-phosphate dehydrogenase showed no special adaptation to low pH values. The results show that the swimbladder epithelium is equipped with enzymes that produce CO2 from glucose without the removal of O2, which is particularly advantageous for creating the high gas partial pressures needed for filling the swimbladder at great depth.

scholarly journals GLUCOSE METABOLISM OF THE SWIMBLADDER TISSUE OF THE EUROPEAN EEL ANGUILLA ANGUILLA

1993 ◽  
Vol 185 (1) ◽  
pp. 169-178 ◽  
Author(s):  
B. Pelster ◽  
P. Scheid
Keyword(s):  
Glucose Uptake ◽  
Venous Blood ◽  
Lactate Concentration ◽  
Lactate Production ◽  
Anguilla Anguilla ◽  
Pentose Phosphate ◽  
Co2 Production ◽  
European Eel ◽  
O2 Uptake ◽  
Lactate Release

Glucose uptake from, and lactate release into, the blood have been analysed in the active gas- depositing swimbladder of the immobilized European eel Anguilla anguilla. Under normoxic conditions, 0.72 micromole min-1 glucose was removed from the blood supply, while lactate was released into it at a rate of 1.16 micromole min-1. The rate of gas deposition into the swimbladder was significantly correlated with the rate of lactate production. Under hypoxic conditions, glucose consumption by, and lactate production of, the swimbladder tissue were reduced, as was the rate of gas deposition. Compared with normoxic conditions, lactate concentration in the swimbladder tissue was elevated after 1 h of hypoxia, indicating a decrease in lactate release. No difference in the osmolality of arterial and venous blood could be detected in these experiments. Combining the data for glucose uptake and lactate release measured under normoxic conditions with the values for O2 uptake and CO2 production of the swimbladder tissue measured under similar conditions in a previous study, a quantitative evaluation of glucose catabolism was performed. According to the O2 uptake of the tissue, only about 1 % of the glucose was oxidized, while about 80 % was fermented to lactic acid. The remaining 0.14 micromole min-1 glucose was presumably catabolized through the pentose phosphate shunt, as indicated by the CO2 production of 0.16 micromole min-1 that cannot be explained by aerobic metabolism.

scholarly journals Inhibition of the pentose phosphate shunt by lead: a potential mechanism for hemolysis in lead poisoning

Blood ◽  
1984 ◽  
Vol 63 (3) ◽  
pp. 518-524 ◽  
Author(s):  
NA Lachant ◽  
A Tomoda ◽  
KR Tanaka
Keyword(s):  
Lead Poisoning ◽  
Lead Acetate ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Pentose Phosphate ◽  
Mechanism Of Inhibition ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Oxidant Sensitivity ◽  
Clinical Lead Poisoning ◽  
Pentose Phosphate Shunt

Abstract Recent investigations have disclosed a decrease in pentose phosphate shunt activity in hereditary pyrimidine 5′-nucleotidase deficiency. Clinical lead poisoning is associated with an acquired decrease in pyrimidine 5′-nucleotidase activity. The current investigations were undertaken (1) to determine if pentose shunt activity was decreased in erythrocytes exposed to lead, and (2) to compare the mechanism of inhibition to that seen in hereditary pyrimidine 5′-nucleotidase deficiency. Normal erythrocytes incubated with lead acetate in vitro demonstrated increased Heinz body formation, decreased reduced glutathione, a positive ascorbate cyanide test, and a reversible suppression of pentose shunt activity in the intact erythrocyte. Lead acetate added to normal red cell hemolysates markedly inhibited the activities of glucose-6-phosphate dehydrogenase (G6PD) and phosphofructokinase. The mean Kis of lead for glucose-6-phosphate and nicotinamide adenine dinucleotide phosphate (NADP) for G6PD were 1.5 microM and 2.1 microM, respectively, which is within the range of intraerythrocytic lead concentrations found in clinical lead poisoning. Magnesium enhanced the ability of lead to inhibit G6PD. Thus, the shortened erythrocyte survival in lead poisoning appears to be due, in part, to increased oxidant sensitivity secondary to inhibition of G6PD and the pentose shunt. The mechanism of shunt inhibition is, in part, similar to that seen in hereditary pyrimidine 5′-nucleotidase deficiency.

scholarly journals Hemolytic anemia in hereditary pyrimidine 5'-nucleotidase deficiency: nucleotide inhibition of G6PD and the pentose phosphate shunt

Blood ◽  
1982 ◽  
Vol 60 (5) ◽  
pp. 1212-1218 ◽  
Author(s):  
A Tomoda ◽  
NA Noble ◽  
NA Lachant ◽  
KR Tanaka
Keyword(s):  
Hemolytic Anemia ◽  
Competitive Inhibitor ◽  
Pentose Phosphate ◽  
Similar Degree ◽  
Phosphogluconate Dehydrogenase ◽  
Noncompetitive Inhibitor ◽  
High Concentrations ◽  
Nucleotide Inhibition ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Pentose Phosphate Shunt

We evaluated the erythrocytes of two patients with hereditary pyrimidine 5′-nucleotidase deficiency. Significant findings included an increased reduced glutathione content, increased incubated Heinz body formation, a positive ascorbate cyanide test, and decreased intraerythrocytic pH. The pentose phosphate shunt activity of the patients' red cells as measured by the release of 14CO2 from 14C-1- glucose was decreased compared to high reticulocyte controls. Glucose-6- phosphate dehydrogenase (G6PD) activity in hemolysates from control erythrocytes was inhibited 43% by 5.5 mM cytidine 5′-triphosphate (CTP) and 50% by 5.5 mM in uridine 5′-triphosphate (UTP) at pH 7.1. CTP was a competitive inhibitor for G6P (Ki = 1.7 mM) and a noncompetitive inhibitor for NADP+ (Ki = 7.8 mM). Glutathione peroxidase, glutathione reductase, and 6-phosphogluconate dehydrogenase were not affected by these compounds. Pentose phosphate shunt activity in control red cell hemolysate at pH 7.1 was inhibited to a similar degree by 5.5 mM CTP or UTP. Since the intracellular concentrations of G6P and NADP+ are below their KmS for G6PD, these data suggest that high concentrations of pyrimidine 5′-nucleotides depress pentose phosphate shunt activity in pyrimidin 5′-nucleotidase deficiency. Thus, this impairment of the pentose phosphate pathway appears to contribute to the pathogenesis of hemolysis in pyrimidine 5′-nucleotidase deficiency hemolytic anemia.

Inhibition of the pentose phosphate shunt by lead: a potential mechanism for hemolysis in lead poisoning

Blood ◽  
1984 ◽  
Vol 63 (3) ◽  
pp. 518-524
Author(s):  
NA Lachant ◽  
A Tomoda ◽  
KR Tanaka
Keyword(s):  
Lead Poisoning ◽  
Lead Acetate ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Pentose Phosphate ◽  
Mechanism Of Inhibition ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Oxidant Sensitivity ◽  
Clinical Lead Poisoning ◽  
Pentose Phosphate Shunt

Recent investigations have disclosed a decrease in pentose phosphate shunt activity in hereditary pyrimidine 5′-nucleotidase deficiency. Clinical lead poisoning is associated with an acquired decrease in pyrimidine 5′-nucleotidase activity. The current investigations were undertaken (1) to determine if pentose shunt activity was decreased in erythrocytes exposed to lead, and (2) to compare the mechanism of inhibition to that seen in hereditary pyrimidine 5′-nucleotidase deficiency. Normal erythrocytes incubated with lead acetate in vitro demonstrated increased Heinz body formation, decreased reduced glutathione, a positive ascorbate cyanide test, and a reversible suppression of pentose shunt activity in the intact erythrocyte. Lead acetate added to normal red cell hemolysates markedly inhibited the activities of glucose-6-phosphate dehydrogenase (G6PD) and phosphofructokinase. The mean Kis of lead for glucose-6-phosphate and nicotinamide adenine dinucleotide phosphate (NADP) for G6PD were 1.5 microM and 2.1 microM, respectively, which is within the range of intraerythrocytic lead concentrations found in clinical lead poisoning. Magnesium enhanced the ability of lead to inhibit G6PD. Thus, the shortened erythrocyte survival in lead poisoning appears to be due, in part, to increased oxidant sensitivity secondary to inhibition of G6PD and the pentose shunt. The mechanism of shunt inhibition is, in part, similar to that seen in hereditary pyrimidine 5′-nucleotidase deficiency.

scholarly journals Hemolytic anemia in hereditary pyrimidine 5'-nucleotidase deficiency: nucleotide inhibition of G6PD and the pentose phosphate shunt

Blood ◽  
1982 ◽  
Vol 60 (5) ◽  
pp. 1212-1218 ◽  
Author(s):  
A Tomoda ◽  
NA Noble ◽  
NA Lachant ◽  
KR Tanaka
Keyword(s):  
Hemolytic Anemia ◽  
Competitive Inhibitor ◽  
Pentose Phosphate ◽  
Similar Degree ◽  
Phosphogluconate Dehydrogenase ◽  
Noncompetitive Inhibitor ◽  
High Concentrations ◽  
Nucleotide Inhibition ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Pentose Phosphate Shunt

Abstract We evaluated the erythrocytes of two patients with hereditary pyrimidine 5′-nucleotidase deficiency. Significant findings included an increased reduced glutathione content, increased incubated Heinz body formation, a positive ascorbate cyanide test, and decreased intraerythrocytic pH. The pentose phosphate shunt activity of the patients' red cells as measured by the release of 14CO2 from 14C-1- glucose was decreased compared to high reticulocyte controls. Glucose-6- phosphate dehydrogenase (G6PD) activity in hemolysates from control erythrocytes was inhibited 43% by 5.5 mM cytidine 5′-triphosphate (CTP) and 50% by 5.5 mM in uridine 5′-triphosphate (UTP) at pH 7.1. CTP was a competitive inhibitor for G6P (Ki = 1.7 mM) and a noncompetitive inhibitor for NADP+ (Ki = 7.8 mM). Glutathione peroxidase, glutathione reductase, and 6-phosphogluconate dehydrogenase were not affected by these compounds. Pentose phosphate shunt activity in control red cell hemolysate at pH 7.1 was inhibited to a similar degree by 5.5 mM CTP or UTP. Since the intracellular concentrations of G6P and NADP+ are below their KmS for G6PD, these data suggest that high concentrations of pyrimidine 5′-nucleotides depress pentose phosphate shunt activity in pyrimidin 5′-nucleotidase deficiency. Thus, this impairment of the pentose phosphate pathway appears to contribute to the pathogenesis of hemolysis in pyrimidine 5′-nucleotidase deficiency hemolytic anemia.

Liver and white muscle protein turnover rates in the European eel (Anguilla anguilla): effects of dietary protein quality

Aquaculture ◽  
1999 ◽  
Vol 179 (1-4) ◽  
pp. 203-216 ◽  
Author(s):  
M. de la Higuera ◽  
H. Akharbach ◽  
M.C. Hidalgo ◽  
J. Peragón ◽  
J.A. Lupiáñez ◽  
...  
Keyword(s):  
Dietary Protein ◽  
Protein Turnover ◽  
White Muscle ◽  
Protein Quality ◽  
Muscle Protein ◽  
Anguilla Anguilla ◽  
European Eel ◽  
Turnover Rates ◽  
Muscle Protein Turnover

Metazoan Parasites and Health State of European Eel, Anguilla Anguilla (Anguilliformes, Anguillidae), From Tonga Lake and El Mellah Lagoon in the Northeast of Algeria

2018 ◽  
Vol 52 (4) ◽  
pp. 279-288 ◽  
Author(s):  
F. Bakaria ◽  
S. Belhaoues ◽  
N. Djebbari ◽  
M. Tahri ◽  
I. Ladjama ◽  
...  
Keyword(s):  
Brackish Water ◽  
Parasite Species ◽  
Anguilla Anguilla ◽  
European Eel ◽  
Health State ◽  
Component Community ◽  
Metazoan Parasites ◽  
Parasite Communities ◽  
High Dominance ◽  
Argulus Foliaceus

Abstract The aim of the study was to examine metazoans parasite communities of European eels (Anguilla anguilla) in freshwater (Tonga Lake) and brackish water (El Mellah lagoon) in the northeast of Algeria. Six parasite taxa were collected: one monogenean, Pseudodactylogyrus sp.; two crustaceans, Ergasilus sp. and Argulus foliaceus; two nematodes, Cucullanus sp. and Anguillicola crassus; one cestode, Bothriocephalus claviceps. Th e most prevalent parasite taxa in freshwater were Pseudodactylogyrus sp., A. crassus and Bothriocephalus claviceps; whereas in the brackish water, eels were infected mainly with A. crassus. Th e characteristics of the parasite component community structure revealed low parasite species diversity and high dominance values in eels from the two localities. Both communities were dominated by a single parasite species: Tonga eels by the monogenean Pseudodactylogyrus sp. and El Mellah lagoon eels by the nematode A. crassus, verified by high Berger-Parker dominance values of 0.76 and 0.87 respectively.

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