Aspartate Transaminase (English: aspartate transaminase, abbreviation? AST), also known as aspartate aminotransferase (SGOT), is a pyridoxal phosphate protein, which can also act on L- phenylalanine, L- tyrosine and L- tryptophan.

Aspartate aminotransferase is one of the liver function tests, which is generally used to test whether the liver tissue is damaged.

mechanism

When myocardial cells are damaged, aspartate aminotransferase will be released into human blood in large quantities, leading to the increase of aspartate aminotransferase in blood; When liver cells are damaged, the value of aspartate aminotransferase in blood will also be detected to increase. However, in the early stage of liver disease and chronic hepatitis, its value is not obviously increased, but it is obviously increased in the late stage of severe liver disease and liver disease.

Generally, the normal value of aspartate aminotransferase is 0 ~ 40u/L (unit per liter).

function

Aspartate aminotransferase can catalyze the transamination of amino groups from aspartic acid to α -ketoglutaric acid, and the products of this reversible amino reaction are oxaloacetic acid and glutamic acid.

Clinical significance

Aspartate aminotransferase, similar to alanine aminotransferase, is a standard for clinical liver function test to determine whether the liver is healthy or not. The difference is that alanine aminotransferase is mainly found in the liver, while aspartate aminotransferase is found in the liver, heart, skeletal muscle, kidney, brain and red blood cells. Generally, it is measured in units of "unit per liter" (U/L).

Extended data:

matters need attention

1, when measuring serum alanine aminotransferase, the substrate and serum should be kept warm in a water bath at 37℃ in advance, and then the substrate should be added to the serum for accurate timing.

2, serum samples should be quickly separated from blood clots, timely determination, if not immediately determined, should be placed in the refrigerator, but not more than 3 days. Hemolytic samples should not be determined, because the activity of intracellular enzymes is high, which will affect the determination results.

3, the operation should accurately grasp the action time, temperature, pH value, reagent concentration and reagent dosage, so as not to affect the determination results.