Serum-cholinesterase activity in health and in liver disease

Abstract

The rates of hydrolysis of acetyl- and benzoyl-choline by normal sera, and by sera from patients having chronic or acute liver damage, were compared. Activity/milliliter of serum was always decreased in chronic liver damage but was frequently within the normal range in acute liver damage. A comparison of the relative rates of hydrolysis of acetyl-, propionyl- and butyryl-choline by sera from normal persons and by sera from patients with chronic liver damage and from patients with acute liver damage showed that, in the 5 cases of chronic liver damage studied, the preferred substrate was always propionylcholine. This was so also in one case of acute liver damage, but the preferred substrate for the sera from the other 5 cases of acute liver damage studied was butyrylcholine. In all the sera examined, normal and pathological, the relative rates of hydrolysis of acetylcholine and butyrylcholine were constant. Activation energies and pH optima for the hydrolysis of acetylcholine and benzoylcholine were measured. The values obtained on the sera from patients having chronic liver damage do not differ greatly from those obtained with normal sera.