Modified heparin-Sepharose procedure for determination of plasma lipolytic activities of normolipidemic and hyperlipidemic subjects after injection of heparin.

A modified heparin-Sepharose affinity chromatography procedure (Boberg et al., J. Lipid Res. 18:544-547, 1977) was developed to determine two different triglyceride lipase activities in human post-heparin plasma: hepatic triglyceride lipase (I) and lipoprotein lipase (II). With this procedure, lipoproteins were separated from the eluted lipases. The total lipolytic activity of II was eluted from heparin-Sepharose by heparin. The use of heparin as eluting agent prevents the partial inhibition of II, in contrast to the procedure based on elution of II with a high concentration of NaCl. In a comparative study with the modified heparin-Sepharose affinity column chromatography, the immunochemical and protamine sulfate inhibition procedures, the results indicated that these three procedures are equally suitable for the determination of I and II from normolipidemic subjects. However, because of possible interference by plasma, the column-chromatographic procedure is the preferred method for measuring lipase concentrations in post-heparin plasma of hyperlipidemic patients. The II activity of post-heparin plasma from normolipidemic subjects was not significantly age-(20-39 and 40-60 years) or sex-related. I activity was also not significantly different with respect to age, but was significantly greater in men than in women.