ALT assays refer to laboratory tests used to measure the activity of alanine aminotransferase (ALT), also known as serum glutamate-pyruvate transaminase (SGPT), in biological samples such as blood. ALT is an enzyme primarily found in the liver, with smaller amounts found in the kidneys, heart, and skeletal muscles.
These assays typically involve measuring the activity of ALT through biochemical reactions. ALT catalyzes the transfer of an amino group from alanine to alpha-ketoglutarate, forming pyruvate and glutamate. The activity of ALT is measured by monitoring the rate of this enzymatic reaction, often using spectrophotometric or colorimetric methods.
ALT assays are commonly performed as part of liver function tests, along with other markers such as aspartate aminotransferase (AST) and alkaline phosphatase (ALP).