Aspartate aminotransferase (AST)
Chemistry ·Also called: AST, SGOT, GOT, aspartate transaminase
What it is
AST sits inside liver cells and also inside skeletal and heart muscle cells. Because it comes from more than one tissue, it is less specific than ALT — but it is released from deeper within the cell, so it can flag more severe damage.
Why your vet measures it
AST is mostly used as a cross-check. Raised AST with raised ALT and normal CK points to the liver. Raised AST with a high CK and a normal ALT points to muscle — after a seizure, a fall, a long period lying down, or a recent injection.
What a high result can mean
- Liver cell damage, usually alongside a raised ALT
- Muscle injury, exertion, seizures, or prolonged recumbency
- Haemolysis in the sample tube, which releases AST and inflates the result artificially
- Heart muscle damage, which is uncommon in dogs and cats
What a low result can mean
- Not clinically significant
Questions worth asking your vet
- Is the CK raised too — could this be muscle rather than liver?
- Was the sample haemolysed?
Related terms
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