alanine transferase
Meaning of alanine transferase: Alanine transferase is a liver enzyme, commonly abbreviated ALT, whose elevated blood level often signals injury to liver cells.
Definition of alanine transferase
Alanine transferase is an enzyme found mainly within liver cells, though smaller amounts are also present in other tissues. Under normal conditions, only a small amount of this enzyme circulates in the blood, since most of it remains inside intact cells rather than being released into circulation.
When liver cells are damaged or destroyed, whether from infection, medication, alcohol use, or another cause, alanine transferase leaks out of the injured cells and into the bloodstream, raising its measured level above the expected range. Because of this, alanine transferase is one of the standard laboratory measurements included when assessing liver health, and a rise in its level is generally interpreted as a marker of liver cell injury rather than of liver function itself.
Alanine transferase is commonly abbreviated ALT, and its older names, serum glutamate pyruvate transaminase and SGPT, still appear occasionally in laboratory reports and older records.
Also known as
Used in a sentence
Laboratory testing showed an elevated alanine transferase level, prompting further evaluation of liver function.
Good to know
An elevated alanine transferase level indicates liver cell injury rather than a measure of how well the liver is functioning overall, a distinction that matters when interpreting liver-related laboratory testing.
Word origin
Where “alanine transferase” comes from
Formed from Latin trans-, meaning across, and ferre, meaning to carry, combined with the suffix -ase, used to name enzymes.