Lactate dehydrogenase-6. A biochemical sign of serious hepatic circulatory disturbance

Insights

Researchers identified a novel lactate dehydrogenase (LD) isozyme band in patients with arteriosclerotic cardiovascular disease. This heat-stable isozyme, composed of M subunits, may indicate a modified LD-5 or alcohol dehydrogenase.

Area of Science:

  • Biochemistry
  • Clinical Chemistry
  • Cardiology

Background:

  • Lactate dehydrogenase (LD) isozymes are crucial biomarkers in diagnosing various diseases.
  • Arteriosclerotic cardiovascular disease can lead to congestive heart failure and organ congestion.
  • Previous research has characterized the standard LD isozyme profiles.

Purpose of the Study:

  • To investigate the presence and characteristics of an additional LD isozyme band in patients with congestive heart failure.
  • To determine the clinical significance and biochemical properties of this novel isozyme.

Main Methods:

  • Agarose gel isozyme electrophoresis was used to separate and identify LD isozymes.
  • Biochemical analyses were performed to assess the isozyme's heat stability, subunit composition, and binding properties.

Main Results:

  • An additional LD isozyme band, cathodic to LD-5, was detected in seven patients.
  • The novel isozyme exhibited extreme heat stability and was not immunoglobulin bound.
  • Biochemical analysis revealed the isozyme contained only M subunits, suggesting it may be a modified LD-5 or alcohol dehydrogenase.

Conclusions:

  • The identified LD isozyme may serve as a potential indicator in patients with severe arteriosclerotic cardiovascular disease and congestive heart failure.
  • Further research is warranted to elucidate the exact nature and clinical utility of this heat-stable, M-subunit-only isozyme.

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