Ast

AST refers to an enzyme (Herold 2022) that catalyzes a reversible transamination between L- aspartate and 2- oxoglutarate to oxaloacetate and L- glutamate (Gressner 2012).

AST, together with ALT (GPT) and GLDH (glutamate dehydrogenase), is an enzyme that acts as an indicator of liver cell damage (Herold 2022).

AST, together with the enzyme ALT, is also referred to as "transaminases" (Kindermann 2007).

It is an enzyme found in a variety of organs including liver, kidney, pancreas, lung, brain, erythrocytes, leukocytes, and cardiac and skeletal muscle, but is not liver specific (Herold 2022).

Within the liver, 80% of AST is found in mitochondria and 20% in cytoplasm (Halwachs- Baumann 2011).

The AST- normal value is < 31 U / l for women and < 35 U / l for men (Lohmann 2020).

AST is primarily used for the early detection of liver and biliary diseases (Lohmann 2020).

An increase in AST can occur due to:

- Hepatitis

- cirrhosis of the liver

- Diseases of the bile ducts

- Diseases of the pancreas

- alcohol or drug consumption (Lohmann 2020)

- physical stress

In a marathon runner, for example, a 2-3 fold increase in AST has been described (Kindermann 2007).

- muscle trauma

- myocardial infarction (Herold 2022)

1. Gressner A M, Arndt T (2012) Lexikon der Medizinischen Laboratoriumsdiagnosti. Volume 1 - clinical chemistry. Springer Verlag Germany / New York 133
2. Herold G et al (2022) Internal medicine. Herold Publishers 516
3. Kasper D L, Fauci A S, Hauser S L, Longo D L, Jameson J L, Loscalzo J et al (2015) Harrison's Principles of Internal Medicine. Mc Graw Hill Education
4. Kindermann W, Dickhuth H H, Nieß A, Röcker K, Urhausen A (2007) Sports cardiology: physical activity in heart disease. Steinkopff Verlag Darmstatdt 121
5. Lohmann M (2020) Understanding laboratory values: blood, urine and stool analyses, normal values at a glance, technical terms and important abbreviations. Mankau- Verlag Murnau Chapter: Physical disorders and organ diseases.