Serum Cholyglycine (CG) is one of the combined cholic acids formed by the combination of cholic acid and glycine. When liver cells are damaged, the ability of liver cells to take up CG decreases, resulting in increased blood CG content; when cholestasis, liver excretion of bile acid is obstructed, and the reflux blood circulation CG content increases, which also increases the blood CG content. As liver cells are damaged to varying degrees, the level of serum CG content is closely related to the extent and degree of liver disease (for reference only).