Activation of lipoprotein lipase increases serum high density lipoprotein 2 cholesterol and enlarges high density lipoprotein 2 particles in rats.

It is known that postheparin plasma lipoprotein lipase (LPL) activity correlates with serum high density lipoprotein cholesterol (HDL-C) levels in humans and animals. Furthermore, LPL has been reported to cause enlargement of HDL particle size in vitro. However, these effects have not yet been experimentally proven. The aim of this study was to determine whether LPL has a role in increase in HDL-C and enlargement of HDL particle by activating the LPL function with NO-1886, the LPL promoting agent. NO-1886 administration increased postheparin plasma LPL activity without influencing hepatic triglyceride lipase activity. NO-1886 increased serum HDL(2)-cholesterol (HDL(2)-C) concentration and enlarged HDL(2) particle size, but did not increase serum HDL(3)-cholesterol concentration or enlarge HDL(3) particle size. Also, serum HDL(2)-C concentrations were positively correlated with HDL(2) particle size (r=0.910). Our study demonstrates that the LPL activation induced with NO-1886 may cause production of HDL(2)-C by catabolism of triglyceride-rich lipoproteins and enlarges HDL(2) particle size in rats.