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Updated: Jul 12, 2026
06:47
Isolation and Analysis of Plasma Lipoproteins by Ultracentrifugation
Published on: January 28, 2021
Abnormal lipoprotein lipase in familial exogenous hypertriglyceridemia
The Journal of Clinical Investigation
|August 1, 1973
Summary
Children with hypertriglyceridemia showed absent postheparin lipolytic activity (PHLA) against chylomicrons. This suggests a specific deficiency in lipoprotein lipase, impacting fat metabolism.
Area of Science:
- Biochemistry
- Genetics
- Metabolic Disorders
Background:
- Hypertriglyceridemia and hepatosplenomegaly are serious conditions affecting lipid metabolism.
- Postheparin lipolytic activity (PHLA) is crucial for clearing triglyceride-rich lipoproteins.
Purpose of the Study:
- To investigate the underlying cause of severe hypertriglyceridemia in two siblings.
- To characterize the postheparin lipolytic activity (PHLA) in affected individuals and their families.
Main Methods:
- Assessed postheparin lipolytic activity (PHLA) against chylomicrons and Intralipid.
- Performed oral glucose tolerance tests and lipoprotein electrophoresis.
- Conducted in vitro studies incubating plasma with chylomicrons.
Main Results:
- Affected siblings had virtually absent PHLA against chylomicrons but normal PHLA against Intralipid.
- Lipoprotein lipase activity was significantly reduced, requiring higher substrate concentrations.
- In vitro studies showed abnormal remnant formation from chylomicrons.
Conclusions:
- The findings suggest a specific defect in lipoprotein lipase, possibly due to a mutant gene affecting substrate specificity.
- An absolute deficiency of normal lipoprotein lipase with compensatory mechanisms is also considered.
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