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Published on: August 5, 2012
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.
Abstract:
I confirmed the existence of an additional isozyme band of lactate dehydrogenase (LD) (EC 1.1.1.27) cathodic to LD-5 utilizing agarose gel isozyme electrophoresis in seven patients. Three of the patients died of circulatory failure within three weeks after the isozyme was identified. Four patients survived after successful therapy for heart failure. The under-lying clinical condition was arteriosclerotic cardiovascular disease causing congestive heart failure with passive congestion of the major viscera. I performed biochemical analysis on the isozyme and found that it was extremely heat stable, was not immunoglobulin bound, and contained only M, not H, subunits. It may represent a posttranslationally modified LD-5 or alcohol dehydrogenase.
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