ASPARTATE AMINOTRANSFERASE (AST, ASPARTATE TRANSAMINASE, SGOT)
A catalytic enzyme found primarily in the heart, liver, and muscle tissue. AST is found in two distinct forms or isoenzymes. c-AST is located in the cytoplasm, and m-AST is found in mitochondria. Increases in the serum total AST level occur any time there is serious damage to cells. In addition, AST may be found in complex with IgA in hepatic cancer. AST is also evaluated in comparison with alanine aminotransferase (ALT) to serially monitor liver damage.