The normal concentrations in the blood are from 5 to 40 U l-1 for AST and from 5 to 35 U l-1 for ALT.
However, when body tissue or an organ such as the liver or heart is diseased or damaged, additional AST and ALT are released into the bloodstream, causing levels of the enzyme to rise.
The normal serum GOT activity ranges from 5.0–13.0 KA units/100 ml