Further studies on the determination of lipase activity

In a previous paper we have discussed Shihabi and Bishop's method for the determination of lipase activity and proposed some modifications. The results of further studies are reported. An initial rise in absorbance which we found with some sera appeared to be caused by an interaction between desoxycholate and lipoproteins; this effect could be removed by treating the sera with dextrane sulphate prior to the determination of the enzyme activity. In urine no lipase activity can be demonstrated; urine contains no inhibitory substances. Red blood cells do not contain lipase and even fairly intense haemolysis does not interfere with our method. Lipase and amylase activities in patients' sera are compared. A good correlation between our method and that of Rick was found.