Importance of molecular charge for the passage of endogenous macromolecules across continuous capillary walls, studied by serum clearance of Lactate Dehydrogenase (LDH) isoenzymes

1983 ◽  
Vol 117 (1) ◽  
pp. 123-130 ◽  
Author(s):  
B. HARALDSSON ◽  
C. EKHOLM ◽  
B. RIPPE
Keyword(s):  
Lactate Dehydrogenase ◽  
Ldh Isoenzymes ◽  
Serum Clearance ◽  
Molecular Charge ◽  
Capillary Walls

Total lactate dehydrogenase and its isoenzymes in serum in the presence of penicillamine and other sulfhydryl compounds.

1977 ◽  
Vol 23 (2) ◽  
pp. 229-233 ◽  
Author(s):  
L L Gershbein ◽  
K G Raikoff
Keyword(s):  
Lactate Dehydrogenase ◽  
Disc Electrophoresis ◽  
The Other ◽  
Rat Serum ◽  
Initial Concentration ◽  
Ldh Isoenzymes ◽  
Allosteric Effectors ◽  
Sulfhydryl Compounds

Abstract Toward delineation of changes in total lactate dehydrogenase (LDH) and in the distribution of LDH isoenzymes as assessed by polyacrylamide disc electrophoresis, we inbucated human and rat sera with various agents, notably sulfhydryl compounds. Although artefacts were apparent when these agents were used without preliminary adjustment of pH, we saw little alteration in total unitage when one or two volumes of serum was mixed with one volume of any of several thiols, especially penicillamine, at an initial concentration of 0.4 mol/liter and pH 7.0-7.5. Under these conditions, penicillamine caused a loss in LDH-5 after incubation for 1 h at 25 degrees C together with small decreases in mobility of the other four isoenzymes toward the anode. A zymosan region appeared below the albumin and tracking dye area. With longer periods of incubation of rat serum with penicillamine or alpha-mercaptosuccinate, a novel band in the zymogram was noted just above the LDH-4 peak. The observations are discussed in terms of allosteric effectors.

Serum lactate dehydrogenase (S-LDH) and S-LDH isoenzymes in patients with testicular germ cell tumors

1983 ◽  
Vol 189 (2) ◽  
pp. 326-333 ◽  
Author(s):  
Finn E. von Eyben ◽  
Gunnar Skude ◽  
Sophie D. Fosså ◽  
Olbjørn Klepp ◽  
Ole Børmer
Keyword(s):  
Lactate Dehydrogenase ◽  
Germ Cell ◽  
Germ Cell Tumors ◽  
Serum Lactate ◽  
Serum Lactate Dehydrogenase ◽  
Testicular Germ Cell Tumors ◽  
Testicular Germ Cell ◽  
Ldh Isoenzymes

A lactate dehydrogenase-immunoglobulin G1 complex, not blocked by anti-idiotype antibody, in a patient with IgG1-lambda type M-proteinemia.

1987 ◽  
Vol 33 (8) ◽  
pp. 1478-1483 ◽  
Author(s):  
K Fujita ◽  
I Sakurabayashi ◽  
M Kusanagi ◽  
T Kawai
Keyword(s):  
Lactate Dehydrogenase ◽  
Complex Formation ◽  
Affinity Chromatography ◽  
Binding Site ◽  
Binding Capacity ◽  
Isoenzyme Pattern ◽  
M Protein ◽  
Light Chains ◽  
Ldh Isoenzymes ◽  
Sepharose 4B

Abstract The serum of a patient with IgG1-lambda type M-proteinemia showed an abnormal isoenzyme pattern for lactate dehydrogenase (LDH, EC 1.1.1.27). By affinity chromatography, we showed that four isoenzymes (LDH2, LDH3, LDH4, and LDH5) were bound to the M-protein. This complex formation was not blocked by anti-idiotype antibody, even though the binding capacity of IgG was exclusively located in the Fab region of the molecule. Moreover, heavy and light chains of the patient's IgG, obtained by reduction, separately had affinities for each of the LDH isoenzymes. LDH-IgG complex was easily dissociated by affinity chromatography on 5'-AMP-Sepharose 4B or by added NADH. We propose the following hypothesis for the LDH-IgG complex formation: LDH can recognize the gamma-Fab region of IgG at the NAD+ binding site of the molecule, but the affinity of the LDH molecule for immunoglobulin is much weaker than that for NADH or 5'-AMP.

scholarly journals Clinical and Diagnostic Significance of Lactate Dehydrogenase and Its Isoenzymes in Animals

2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Robert Klein ◽  
Oskar Nagy ◽  
Csilla Tóthová ◽  
Frederika Chovanová
Keyword(s):  
Lactate Dehydrogenase ◽  
Cell Injury ◽  
The Body ◽  
Isoenzyme Pattern ◽  
Diagnostic Significance ◽  
Ldh Isoenzymes ◽  
Body Tissues ◽  
Organ Tissue ◽  
Lactate Dehydrogenases

Lactate dehydrogenase (LDH) is widely distributed enzyme in cells of various living systems where it is involved in carbohydrate metabolism catalyzing interconversion of lactate and pyruvate with NAD+/NADH coenzyme system. Cells of tissues are direct source of lactate dehydrogenase isoenzymes that are naturally distributed in blood plasma/serum of animals and humans producing characteristic profile. This profile depends on intracellular isoenzyme concentration in all tissues that contribute to the common pool of lactate dehydrogenases in plasma/serum as a consequence of natural cell degradation. LDH is widely distributed in the body, high activities are found in the heart, liver, skeletal muscle, kidney, and erytrocytes, whereas lesser amounts are found in the lung, smooth muscle, and brain. Because of its widespread activities in numerous body tissues, LDH is elevated in a variety of disorders. There are many conditions that contribute to increased activity of LDH. An elevated total LDH value is a rather nonspecific finding. Therefore, LDH assays assume a more clinical significance when separated into isoenzyme fractions. The activity of LDH and its serum and tissue patterns and composition show great variations between the species. These differences do not allow using catalytic activities of LDH isoenzymes from one species to another. Instead, the pattern of serum LDH isoenzymes should be interpreted in respect to its species origin that is important in particular in veterinary medicine. Determination of total LDH activity and its isoenzyme pattern in serum of mammals had become one of the biochemical indicators in the assessment of organ disorders. When the content of cells is released from tissue to plasma, as on cell injury, the LDH isoenzyme pattern of the serum changes in favour of the profile of the affected organ (tissue) that can be used in the diagnostic practice.

Production of monoclonal antibodies to lactate dehydrogenase (LDH) isoenzymes for immunohistochemical study on fixed tissue section

1989 ◽  
Vol 21 (11) ◽  
pp. 638-644 ◽  
Author(s):  
Langxing Pan ◽  
Peter C. L. Beverley ◽  
Lynda G. Bobrow ◽  
Dallas M. Swallow ◽  
Peter G. Isaacson
Keyword(s):  
Monoclonal Antibodies ◽  
Lactate Dehydrogenase ◽  
Tissue Section ◽  
Immunohistochemical Study ◽  
Fixed Tissue ◽  
Ldh Isoenzymes

scholarly journals Diagnostic utility of measuring lactate dehydrogenase levels and its isoenzyme activities for the evaluation of malignancy in feline pleural effusion and ascitic fluid

2021 ◽  
Author(s):  
Eiji Naito ◽  
Roka Shimada ◽  
Masashi YUKI
Keyword(s):  
Lactate Dehydrogenase ◽  
Pleural Effusion ◽  
Infectious Diseases ◽  
Ascitic Fluid ◽  
Roc Analysis ◽  
Operating Characteristic ◽  
Diagnostic Utility ◽  
Malignant Effusion ◽  
Ldh Isoenzymes ◽  
Auc Value

Abstract Lactate dehydrogenase (LDH) isoenzymes may be useful in the differential diagnosis of pleural effusion (PE) and ascitic fluid (AF) etiologies in cats since tissue damage induces their release, thereby changing the pattern of their activity. The present study aimed to determine the diagnostic utility of measuring LDH levels and its isoenzyme activities in PE or AF in cats with malignancy. We measured LDH levels and its isoenzyme activities in serum, PE, and AF in 29 cats and compared the results between malignant, infectious diseases, and non-malignant, non-infectious diseases. Receiver operating characteristic (ROC) analysis was performed to assess the accuracy of the tests in diagnosing feline malignancy. In PE or AF, significant differences were found in LDH levels and LDH isoenzymes activities among the three groups. The combination of LDH level and LDH-1 activity in PE or AF had the highest area under the ROC (AUC) value of 0.874 for discriminating malignant effusion from non-malignant effusion. The sensitivity and specificity of using the combination of LDH level (cutoff: <2,269 U/L) and LDH-1 activity (cutoff: <4.8%) in PE or AF for predicting malignancy with the highest AUC value were 94.4% and 72.7%, respectively. Our results suggest that the combination of LDH level and LDH-1 activity in PE or AF can potentially diagnose for malignancy. Considering that LDH isoenzymes can be measured inexpensively and easily, LDH tests can be readily accommodated in veterinary clinical practice.

Optimum Reaction Conditions for Human Lactate Dehydrogenase Isoenzymes as They Affect Total Lactate Dehydrogenase Activity

1968 ◽  
Vol 14 (8) ◽  
pp. 740-753 ◽  
Author(s):  
Royal J Gay ◽  
Robert B McComb ◽  
George N Bowers
Keyword(s):  
Lactate Dehydrogenase ◽  
Comparative Study ◽  
Substrate Concentration ◽  
Spectrophotometric Assay ◽  
Serum Samples ◽  
Reaction Conditions ◽  
Lactate Dehydrogenase Activity ◽  
Ldh Isoenzymes ◽  
Optimum Reaction ◽  
Lactate Dehydrogenase Isoenzymes

Abstract Optimum reaction conditions at 30° ± 0.5° for two continuous spectrophotometric assay procedures, lactate to pyruvate (L → P) and pyruvate to lactate (P → L), were determined with respect to pH at 30° (pH30) substrate concentration, and coenzyme concentration for the human LDH isoenzymes. For the P → L procedure, broad pH30 optima were within the range of 7.20-7.40 for all the LDH isoenzymes. The coenzyme optima were identical for all of the isoenzymes tested at a reduced NAD concentration of 1.5 x 10-4 M. Pyruvate substrate optima ranged from 7.5 x 10-4 M for LDH1 to 1.7 x 10-3 M for LDH5 at pH30 7.30. For the L → P procedure, the pH30 optima were within the range of 8.30-8.88 for the LDH5 through LDH1 isoenzymes, respectively. Optimum activity was obtained at a NAD concentration of 6.0 x 10-3 M and remained constant at least to 1.8 x 10-2 M for each of the isoenzymes tested. L-Lactate substrate optima ranged from 4.0 x 10-2 M for LDH1 to at least 7.2 x 10-2 M for LDH5. From the isoenzyme studies, the degree of variation possibly involved in either method due to variations in isoenzyme distribution was calculated for total LDH samples. These calculations showed that both methods, P → L and L → P, were essentially equivalent. This equivalency was verified by a comparative study of the two methods on human serum samples.

Phosphotyrosine-containing lactate dehydrogenase is restricted to the nuclei of PC12 pheochromocytoma cells

1990 ◽  
Vol 10 (2) ◽  
pp. 770-776
Author(s):  
X H Zhong ◽  
B D Howard
Keyword(s):  
Lactate Dehydrogenase ◽  
Cell Transformation ◽  
Lactate Metabolism ◽  
Wild Type ◽  
Altered Expression ◽  
Pheochromocytoma Cells ◽  
Ldh Isoenzymes ◽  
Tumor Viruses ◽  
A Subunit ◽  
Pc12 Pheochromocytoma Cells

There are five lactate dehydrogenase (LDH) isoenzymes, composed of various combinations of two types of subunits. LDH-5, which contains only the LDH A subunit, is known to be present in both the cytoplasm and the nucleus, to act as a single-stranded DNA-binding protein possibly functioning in transcription and/or replication, and to undergo phosphorylation of tyrosine 238 in approximately 1% of the enzyme after cell transformation by certain tumor viruses. We have characterized LDH from wild-type PC12 pheochromocytoma cells and from a PC12 variant (MPT1) that exhibits altered lactate metabolism and altered expression of multiple genes. Wild-type and MPT1 cells contain different proportions of LDH isoenzymes, with LDH-5 being more predominant in wild-type cells than in the variant. A small fraction of LDH from PC12 cells contains phosphotyrosine. Approximately 99% of the total LDH activity is located in the cytoplasm, but all of the phosphotyrosine-containing LDH is located in the nucleus. Furthermore, essentially all of the nuclear LDH contains phosphotyrosine. These results suggest that tyrosine phosphorylation can affect its role in the nucleus.

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