Medical expert of the article
New publications
Isozyme 1 lactate dehydrogenase in the blood
Last reviewed: 23.04.2024
![Fact-checked](/sites/default/files/fact-checked.png)
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
The reference values (norm) of lactate dehydrogenase 1 activity are 15-25% of the total lactate dehydrogenase activity in blood serum.
Isoferments of lactate dehydrogenase are contained in tissues in a strictly defined ratio, that is, each tissue, including blood, has a characteristic spectrum of lactate dehydrogenase isoenzymes. In a number of pathological conditions, when permeability of cell membranes increases in one or another organ and tissue damage occurs, lactate dehydrogenase isoenzymes in excess amount enter the blood. Since the activity of isoenzymes in tissues is several hundred times higher than their activity in serum, the spectrum of lactate dehydrogenase isoenzymes in it becomes similar to the spectrum of lactate dehydrogenase isoenzymes in the affected organ. In normal serum the ratio of isozymes of lactate dehydrogenase activity include LDH 1 - 15-25% of total activity, LDH 2 - 30-40%, LDH 3 - 20-25%, LDH 4 - 10-15%, LDH 5 - 5- 15%.