A radiochemical test for phospholipase A2 catalytic activity.

A position-specifically labelled phosphatidylcholine is the substrate for the selective determination of Phospholipase A2 in serum, ascites and tissue samples. Optimal reaction conditions and simplifications of handling are discussed. A control group of human serum samples ranged up to 2.1 U/l. The maximum serum activity in samples of patients with acute pancreatitis was 126 U/l. In human ascites activities up to 380 U/l were measured. The method described here turned out to be a practicable instrument for the determination of phospholipase A2 activity using only commercially available reagents.