Lipoprotein lipase activity in bovine aorta.
A lipoprotein lipase in the bovine arterial wall has been identified and partially characterized. The enzyme has a Km apparent of 1 mM for triolein in a phosphatidylcholine stabilized emulsion. The lipase was stimulated 20- to 30-fold by the addition of heated rat plasma to the assay medium. The activity exhibited a pH optimum at 8.6. Protamine sulfate (1.0 mg/ml) inhibited the activity by 50%, whereas 1.4 M sodium chloride inhibited by 85%. Sodium fluoride, an inhibitor of the hormone-sensitive lipase, had no effect on the activity. Additions of low concentrations of heparin or Ca-2+ to the enzyme caused a slight stimulation of the lipolytic activity. A crude sectioning of the aorta revealed specific activity of lipoprotein lipase to be highest at the endothelial side of the artery.
D000818:Animals; D001011:Aorta / Q000201:enzymology*; D001769:Blood; D002118:Calcium / Q000494:pharmacology; D002417:Cattle / Q000378:metabolism*; D003864:Depression, Chemical; D004727:Endothelium / Q000201:enzymology; D005459:Fluorides / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008071:Lipoprotein Lipase / Q000378:metabolism*; D010713:Phosphatidylcholines; D011479:Protamines / Q000494:pharmacology; D012965:Sodium Chloride / Q000494:pharmacology; D014304:Triolein
D010713:Phosphatidylcholines; D011479:Protamines; D014304:Triolein; D012965:Sodium Chloride; D006493:Heparin; D008071:Lipoprotein Lipase; D005459:Fluorides; D002118:Calcium