Lipoprotein lipase is a key enzyme in the regulation of lipid fuel disposal,3 and it provides fatty acids for tissue utilization by catalyzing the hydrolysis of triacylglycerol circulating in triglyceride-rich lipoproteins. Anchored to the surface of the capillary endothelium by glycosaminoglycans, lipoprotein lipase hydrolyzes plasma chylomicrons and VLDL to remnant particles. As such, lipopro...

We compared two methods for the direct selective measurement of hepatic lipase and lipoprotein lipase activities in human plasma after intravenous administration of heparin. Except for the emulsifier (gum arabic vs lecithin), the two assay media for hepatic lipase are essentially similar. Results for hepatic lipase by these two assays correlate well (r = 0.99). The assays for lipoprotein lipase...

Hormone-sensitive lipase and cholesterol ester hydrolase of chicken adipose tissue were markedly activated by adenosine 3’:5’-monophosphate (CAMP)-dependent protein kinase (on the average, 235 to 275%); occasionally as much as 1000%). Diglyceride and monoglyceride hydrolases were also activated, but to a lesser extent (60 to 87%). The activation of all four hydrolases was inhibited by protein k...

Lipoprotein lipase released from the rat heart during a 30-s perfusion with heparin was compared to the lipase remaining in the heart tissue. The perfusate, containing the heparin-releasable enzyme, as well as the heart tissue extract ("residue"), was purified on heparin-Sepharose affinity columns. Both purified fractions showed pronounced inhibition by 1 M NaCl and by antiserum to heart lipopr...

We studied the effects of very low density lipoprotein (VDL) obtained from hypertriglyceridemic subjects on the secretion of lipoprotein lipase and lipid accumulation in human monocyte-derived macrophages. The incubation of macrophages with VLDL obtained from different subjects caused different effects on the secretion of lipoprotein lipase (6.8 to 137.7 nM free fatty acid/min/mg cell protein) ...

A severe hyperlipemia in mink, with a pattern that suggested recessive inheritance, was observed at a farm in Norway. On a normal mink diet, affected animals had grossly elevated levels of plasma triglycerides which decreased towards normal on a low-fat diet. Normal minks had the main part of their plasma cholesterol in the HDL fraction. Affected minks, although severely hypertriglyceridaemic, ...

Hepatic lipase plays a key role in the turnover of potentially atherogenic lipoprotein remnants and in determining the relative distribution of high density lipoprotein (HDL) particle size subclasses. Rabbits fed a cholesterol-enriched diet have been found to accumulate potentially atherogenic chylomicron remnants and beta-very low density lipoprotein (beta-VLDL) and show a rapid increase in li...

The new photometric lipase determinations use diacylglycerols as substrates in a micellar solution, whereas the turbidimetric method is based on emulsified triacylglycerols degradation. Extrahepatic lipoprotein lipase, which is well known to be liberated by heparin from the capillar binding sites, may cleave triacylglycerols as well as diacylglycerols. When a heparin bolus injection is given to...

The freshly secreted milk of goats has been shown (McCarthy & Patton, 1964; Christie, 1974) to catalyse a number of enzymic reactions of lipogenesis. Further experiments showed these activities to be localized in closed vesicular structures present in the milk. Their properties indicate that they originate from the mammary epithelium (Christie & Wooding, 1975); they are, effectively, anucleate ...

1. Lipoprotein lipase activity was measured in heart homogenates and in heparin-releasable and non-releasable fractions of isolated perfused rat hearts, after the intravenous injection of Triton WR-1339. 2. In homogenates of hearts from starved, rats, lipoprotein lipase activity was significantly inhibited (P less than 0.001) 2h after the injection of Triton. This inhibition was restricted excl...