Glutamine aminotransferase, 40 U/L, is a normal presentation and does not require treatment. Glutamine transaminase (AST), also known as aspartate aminotransferase, catalyzes the aminotransfer reaction between L-aspartate and α-ketoglutarate.AST is found primarily in the myocardium, and to a lesser extent in the liver, skeletal muscle, and renal tissues.The normal value of AST is 0-40 U/L. When liver cells are damaged, AST is released into the plasma, resulting in elevated blood AST concentrations. The normal value of AST is 0~40U/L. When hepatocyte injury occurs, AST is released into the plasma, resulting in an increase in blood AST concentration.Elevated AST is commonly seen in viral hepatitis, alcoholic liver disease, cirrhosis, and other liver diseases, and can also be seen after acute myocardial infarction. An AST of 40 U/L is within the normal range and is generally not considered liver disease. If AST elevation occurs, you should consult a doctor in time to clarify the cause of the disease and treat it under the doctor’s guidance.