Mechanism of action of lipoprotein lipase and hepatic triglyceride lipase.
Lipoprotein lipase (LPL) and hepatic triglyceride lipase (H-TGL) were isolated from human postheparin plasma, and their interfacial properties were examined with mixed monolayers of trioleoylglycerol and phosphatidylcholine. LPL showed a surface pressure optimum between 20 and 22 mN/m, whereas H-TGL activity decreased at lipid packing densities of greater than 20 mN/m. LPL activity toward monolayers containing 2 mol percent trioleoylglycerol was enhanced 2.6-fold by the addition of 5 mol percent cholesteryl oleate; cholesteryl ester had no effect on H-TGL activity. We suggest that differences in interfacial properties account for the lipoprotein specificity of these lipolytic enzymes.
D002384:Catalysis; D002788:Cholesterol Esters / Q000097:blood / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D008049:Lipase / Q000097:blood / Q000378:metabolism*; D008071:Lipoprotein Lipase / Q000097:blood / Q000378:metabolism*; D008079:Lipoproteins, VLDL / Q000097:blood / Q000378:metabolism; D008099:Liver / Q000201:enzymology*; D014280:Triglycerides / Q000097:blood / Q000378:metabolism
D002788:Cholesterol Esters; D008079:Lipoproteins, VLDL; D014280:Triglycerides; D008049:Lipase; D008071:Lipoprotein Lipase