Overproduction of a kinetic subclass of VLDL-apoB, and direct catabolism of VLDL-apoB in human endogenous hypertriglyceridemia: an analytical model solution of tracer data

Journal Article · Sat Oct 01 04:00:00 EDT 1983 · J. Lipid Res.; (United States)

OSTI ID:6747390

Eaton, R P; Allen, R C; Schade, D S

To investigate the participation of the major apoprotein involved in triglyceride transport in the pathogenesis of endogenous hypertriglyceridemia, five kinetic studies of apoprotein B were conducted in volunteer normolipidemic subjects and six studies in four patients with endogenous hypertriglyceridemia. The transport of apoprotein B within four kinetic subclasses of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) was studied by injection of (/sup 75/Se)selenomethionine. A 24-fold increase in the entry of newly synthesized apoprotein B at the initial kinetic subclass of the four-compartment VLDL delipidation sequence characterized the hypertriglyceridemic studies relative to normal subjects. Moreover, approximately 75 mg/kg per day of VLDL-B turnover reflected direct catabolism independent of conversion to IDL and/or to LDL, in contrast to the 8 mg/kg per day observed in controls. IDL-B was derived from VLDL-B in both normal and hypertriglyceridemic subjects, and was responsible for greater than 70% of all LDL-B synthesis. LDL-B pool size and turnover were indistinguishable in hypertriglyceridemic subjects from that observed in normal subjects. These studies suggest that two kinetic phenomena may characterize the pathophysiology of endogenous hypertriglyceridemia: a) over-production of apoB within a kinetic subclass of VLDL and b) preferential catabolism of hypertriglyceridemic VLDL without prior conversion to IDL/LDL.

• Research Organization: Univ. of New Mexico, Albuquerque
• OSTI ID: 6747390
• Journal Information: J. Lipid Res.; (United States), Journal Name: J. Lipid Res.; (United States) Vol. 24:10; ISSN JLPRA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
550901 -- Pathology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
BETA DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CATABOLISM
DAYS LIVING RADIOISOTOPES
DISEASES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ESTERS
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIPIDS
LIPOPROTEINS
LIPOTROPIC FACTORS
MEMBRANE TRANSPORT
METABOLIC DISEASES
METABOLISM
METHIONINE
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PATHOGENESIS
PROTEINS
RADIOISOTOPES
SELENIUM 75
SELENIUM ISOTOPES
TRACER TECHNIQUES
TRIGLYCERIDES