Lactic dehydrogenase

Another interesting sperm specific antigen is lactic dehydrogenase-x (LDH-x or LDHC, an isoenzyme of LDH confined to male germ ceUs. 

Lactic Dehydrogenase (LD). LD catalyzes the reversible conversion of lactate to pyruvate in the presence of MAD ... 

The resulting pyruvate may be measured by coupling the reaction with lactic dehydrogenase and NADH, or chemically by using dini-trophenylhydrazine. The kinetic method has been revised by Henry and co-workers to optimize the analytical conditions, and still is the method of choice (28). 

Amador, E. Dorfman, L. E. and Wacker, W. E. C. Serum lactic dehydrogenase activity. An analytical assessment of current assays. Clin. Chem. (1963), , 391-399. 

Amador, E., Reinstein, H. and Benotti, N. Precision and accuracy of lactic dehydrogenase assays. Am. J. Clin. 

Vessel, E. S., and Bearn, A. G. Observations on the heterogeneity of malic and lactic dehydrogenase in human serum and red blood cells. J. Clin. Invest. 

Catalysis by flavoenzymes has been reviewed and various analogues of FAD have been prepared e.g. P -adenosine-P -riboflavin triphosphate and flavin-nicotinamide dinucleotide ) which show little enzymic activity. The kinetic constants of the interaction between nicotinamide-4-methyl-5-acetylimidazole dinucleotide (39) and lactic dehydrogenase suggest the presence of an anionic group near the adenine residue at the coenzyme binding site of the enzyme. ... 

Lactic dehydrogenase Serum Harp seal Yes Increased Ronald et al. (1977)... 

Cyprinus carpio 0.5 after 6 days, 300% increase in phosphorylase and 200% increase in glucose-6-phosphatase activities in liver increase in sugar level and serum lactic dehydrogenase activity 18... 

Hemolytic anemias tend to be normocytic and normochromic and to have increased levels of reticulocytes, lactic dehydrogenase, and indirect bilirubin. 

Prognosis depends on histologic subtype and clinical risk factors (e.g., age more than 60 years, performance status of 2 or more, elevated lactic dehydrogenase, extranodal involvement, and stage III or IV disease). These risk factors are used to calculate the International Prognostic Index. 

Km is the Michaelis constant. In some cases such as hydrolases or lactic dehydrogenases (T2), the velocity may fall again with higher substrate concentrations, so that there is an optimum substrate concentration which approximates the theoretical value V, the maximal velocity, following the theory of Michaelis and Menten... 

Glucose Lactic dehydrogenase (LDH) Phosphorus Potassium Serum glutamic-oxaloacetic transaminase (SGOT) Serum glutamic-pyruvic transaminase (SGPT) Sodium Total bilirubin Total cholesterol Total protein Triglycerides White cell differential count ... 

Hepati c 1 (significantly increased relative liver weight significantly increased serum lactic dehydrogenases) ... 

Abston PA, Yarbrough JD. 1974. The in vivo effects of dietary mirex on hepatic lactic dehydrogenase and glutamic oxaloacetic transaminase levels in the rat. J Agric Food Chem 22 66-68. 

The generalization that the same dehydrogenase has the same stereospecificity, no matter what the source of the enzyme, has been tested now particularly well for malic and lactic dehydrogenases. In fact, one can venture a guess, that pyridine nucleotide dehydrogenases which oxidize a-hydroxycarb oxylic acids at the a-position, all have A stereospecificity for the pyridine nucleotide, regardless of their stereo-specificity for the substrate. Biellman and Rosenheimer 88> have assembled the data. One can add liver malic enzyme 90> to their list. 

Diagrammatic representation of anticipated substrate binding in the active ternary intermediate of the lactic dehydrogenase reaction. The numbers refer to specific amino acid residues in the peptide chain of the protein. 

Stereoview of the a-carbon models of the subunits of s-malic dehydrogenase (sMDH) and lactic dehydrogenase (LDH). 

Hepatic Effects. Both patients described by Letz et al. (1984) (see Section 2.2.3.1) had elevated serum aspartate aminotransferase and lactic dehydrogenase, indicating severe hepatic damage. 

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