Electrophoretic fractionation of pancreatic lipase.

Human pancreatic isolipases were separated by electrophoresis on cellulose acetate membrane. Band visualization by fluorescence detection of NADH produced by beta-oxidation cyclic reaction of fatty acid liberated from 1,2-dilinoleoylglycerol by lipase was achieved by making a two-plate "sandwich" of an electrophoresis plate and a substrate-bearing plate. Two true lipase forms, named L1 and L2 to reflect their electrophoretic migration, were resolved with this method and quantified by densitometry. The procedure was not only simple and rapid but also precise (between-run CV less than 13.5%) and sensitive (detected lipase fractions of less than 2 U/L). L1 (mean 57% of total lipase, SD 19.3%) and L2 (mean 43%, SD 19.3%) lipase forms were found in all normal persons studied. In a preliminary clinical study of 27 emergency room patients, evaluation of the lipase electrophoretic pattern in serum did not separate patients with acute pancreatitis from those with other acute abdominal disorders.