Isozymes of lactic dehydrogenase in human tissues.

Serum lactic acid dehydrogenase isozyme determination in myocardial infarction.

Introduction The principle of electrophoresis is known to be of great use in today's medicine and an expanding literature on this subject supports this view. Various methods for the electrophoretic separation of charged molecules have been developed in the past 15 years. Immunological and physicochemical studies have further increased knowledge of these electrophoretic fractions. On this princi...

Lactic Dehydrogenase Isozymes

Lactic dehydrogenase isozymes (I-lactate, NAD oxidoreductase), which are key enzymes in glycolysis, have been the object of extensive investigation. Five LDH isozymes have been found. The five isozymes represent the five possible tetramaric combinations of the two polypeptides. Thus, the five tetramers range from LDH-l( H4 ) to LDH -5 ( M4 ), the three hybrid enzymes being H3MI, H2 M2, and H j ...

Genetic Evidence for the Subunit Structure of Lactate Dehydrogenase Isozymes.

The lactate dehydrogenases commonly occur in from one to five molecular forms (isozymes) in the various tissues of an animal species.' By means of zone electrophoresis, characteristic patterns of these isozymes may be demonstrated in each tissue. In adult animals, most tissues contain all five isozymes but in different proportions. Usually, heart muscle exhibits principally the first, or most n...

Pyridine nucleotide-linked dehydrogenases and isozymes of normal rat breast and growing and regressing breast cancers.

Four pyridine nucleotide-linked dehydrogenases, glucose-6phosphate dehydrogenase (G6PDH),3 isocitric dehydrogenase (ICDH), lactic dehydrogenase (LDH), and malic dehydrogenase (MDH), and their isozymes have been studied in the normal virgin rat breast, in the breast of tumor-bearing rats, in the breast cancers themselves, and in these tissues following ovariectomy. Enzyme activity expressed per ...

Isozymes of lactate dehydrogenase (LDH) in skeletal tissues of the embryonic and newly hatched chick.

Multiple forms of lactic dehydrogenase in tissues of the mouse: their specificity, cellular localization, and response to altered physiological conditions.

There is increasing evidence that many enzymes exist in tissues and cells in multiple molecular forms (Markert and Moller, 1959). Of less certainty, however, is the question of differences between these multiple molecular forms in terms of their catalytic and physiological activities. Indeed Markert and Moller felt that these forms, termed isozymes, possessed identical substrate specificities a...