We use cookies to help us improve the website and your experience using it. You may delete and block all cookies from this site at any time. However, please note this may result in parts of the site no longer working correctly. If you continue without changing your settings we will assume you are happy to receive all cookies on this site.


Aspartate Aminotransferase; AST

Pseudonyms: Systematic name L‐aspartate:2‐oxoglutarate aminotransferase (EC2.6.1.1); also oxaloacetate aminotransferase, glutamate oxaloacetate aminotransferase; formerly known as aspartate transaminase and SGOT.

General information

Collection container:

Adults - serum (with gel separator, 4.9mL Sarstedt brown top).

Paediatrics - lithium heparin plasma (1.2mL Sarstedt orange top tube).

Type and volume of sample: The tubes should be thoroughly mixed before transport to the lab. The test may be added to a profile without provision of a separate specimen provided a full tube has been received. This test is NOT included in the standard liver function profile.

Specimen transport/special precautions: N/A

Laboratory information

Method principle:

Aspartate + 2‐oxoglutarate → (AST) → oxaloacetate + glutamate

Oxaloacetate + NADH + H+ → (MD) → malate + NAD+

Pyridoxine 5'‐phosphate is a coenzyme for the AST reaction; its addition to the reaction mixture ensures that all the apoenzyme is catalytically active and measured.

Biological reference ranges:

Up to 14D 20-98 IU/L
Up to 3yrs 16-69 IU/L
>3 years Male <50 IU/L
Female <35 IU/L

Turnaround times: Results are available within 1 hour (urgent - for paeds please phone lab in advance of sampling) or 4 hours (routine).

Clinical information

Used in similar fashion to ALT i.e. to detect hepatotoxicity. However, there is less hepatic specificity to AST compared with ALT. The ALT/AST ratio is sometimes used to implicate alcoholic liver disease in symptomatic individuals.

Tissue specificity: the relative activity of AST in various tissues (where plasma = 1) is: liver 2850x; kidneys 1200x; heart 450x; skeletal muscle 300x.


(Last reviewed 25th June 2017)