What does AST stand for?

Study liver anatomy and function with our medical students test. Engage with detailed multiple choice questions, each with hints and explanations. Prepare effectively for your test!

AST stands for aspartate aminotransferase, an enzyme that facilitates the transfer of an amino group from aspartate to alpha-ketoglutarate, forming oxaloacetate and glutamate. This enzyme is abundant in multiple tissues, especially the liver, heart, skeletal muscle, and kidneys, which is why elevations in AST can reflect injury in various organs rather than liver injury alone. In clinical practice, AST is often measured together with alanine aminotransferase (ALT) as part of liver function tests. ALT is more liver-specific, whereas AST can be elevated for reasons beyond the liver, such as muscle injury. A notable pattern in liver disease is when the AST level is disproportionately elevated relative to ALT, a scenario sometimes seen in alcoholic liver disease (often with an AST:ALT ratio greater than 2:1), though this is just one piece of the broader diagnostic picture. The other enzyme names correspond to the remaining options: alanine aminotransferase, alkaline phosphatase, and gamma-glutamyl transferase.