Several main serum enzyme indexes in blood test

Release time:

2020-09-08


Usually when we go to the hospital for an examination, the indispensable thing is to draw blood with a vacuum blood collection tube. The most common examinations are routine blood (blood cell) examination, four items of coagulation, erythrocyte sedimentation rate test and blood gas analysis. However, in addition to blood cells, fibrinogen, water and inorganic salts, there are a small amount of enzyme proteins in the blood. The examination of these enzyme indicators is also of great significance.

Although there are few enzymes in the blood, these enzymes can accurately reflect the changes in the body's metabolism, which is also very important for the judgment of many diseases or physical conditions. Here are several main serum enzyme indicators.

Serum aminotransferase:

Transaminase is a class of enzymes that catalyze the amino transfer between amino acids and keto acids, with alanine aminotransferase (GPT or ALT) and aspartate aminotransferase (GOT) being the most important. The intracellular concentration of ALT is 1000-3000 times higher than that in serum. As long as 1% of hepatocytes are destroyed, serum enzymes can be doubled. It is recommended by WHO as the most sensitive detection index for liver damage.

When the human body exercises vigorously, the permeability of the cell membrane changes and the muscle system releases more aminotransferases. Therefore, it should be ruled out that the patient was tested by blood sampling after strenuous exercise.

 

Serum enzyme index inspection of vacuum blood collection tube

The content of aspartate aminotransferase (AST) in human red blood cells is nearly 40 times higher than that in plasma, so serum aminotransferase can increase during hemolysis. Therefore, a vacuum blood collection tube with serum separating gel should be used to collect blood, and the serum should be centrifuged as soon as possible to avoid hemolysis.

Serum lactate dehydrogenase (LDH):

It is a metal protein containing zinc ions, one of the important enzymes for anaerobic glycolysis and gluconeogenesis. It can catalyze the reduction and oxidation reaction between propionic acid and L-lactic acid, as well as related α-ketones. acid. As with aminotransferases, attention should also be paid to the false elevation caused by strenuous exercise and hemolysis.

Pregnant women's serum LDH will increase. Platelets must be centrifuged at high speed in anticoagulated blood prepared from heparin, citrate or ethylenediaminetetraacetic acid (EDTA), otherwise the plasma still contains platelets, which can increase LDH. In addition, the LDH of young children is higher than that of adults. Giant LDH can cause a false increase in enzyme activity. The maximum LDH fluctuation range of the same person in one day is 30%.

Oxalate can inhibit the activity of LDH, so LDH cannot be measured when preparing plasma with such anticoagulants, such as blood samples collected from potassium oxalate-sodium fluoride anticoagulation tubes.

In addition to the above-mentioned enzyme indexes, there are alkaline phosphatase (ALP), serum γ-glutamyl transpeptidase (GGT), serum cholinesterase (ChE), etc. in the serum. When checking these enzyme indexes Pay attention to whether it is a physiological abnormality or a pathological abnormality. Desheng is a veteran manufacturer of blood test reagents with more than ten years of experience. Welcome everyone to come and communicate.