Alanine transaminase (
ALT) is a
transaminase enzyme . It is also called
alanine aminotransferase (
ALAT) and was formerly called serum glutamate-pyruvate transaminase (SGPT) or serum glutamic-pyruvic transaminase (SGPT). ALT is found in
plasma and in various body tissues, but is most common in the
liver. It catalyzes the two parts of the
alanine cycle. Serum ALT level, serum AST (
aspartate transaminase) level, and their ratio (
AST/ALT ratio) are commonly measured clinically as
biomarkers for liver health. The tests are part of
blood panels.