Determinants of fasting plasma triglyceride levels: metabolism of hepatic and intestinal lipoproteins.
The contribution of the kinetics of exogeneous and endogenous lipoproteins in determining the level of triglyceride in fasting plasma was assessed in a group of 19 normolipidaemic and hypertriglyceridaemic subjects. From data derived during a 9-h infusion of [15N]-glycine, we have assessed very low density lipoprotein apolipoprotein B production, and from data analysed by kinetic modelling obtained following ingestion of retinol and triolein, we have assessed chylomicron and chylomicron remnant clearance in a group of 19 normolipidaemic and hypertriglyceridaemic subjects. A strong positive correlation was observed between the fasting plasma triglyceride level and the reciprocal of the apolipoprotein B fractional synthetic rate (r = 0.83, P less than 0.01). A positive correlation was also found with the rate of clearance of chylomicron remnants (Sf 20-400; r = 0.87, P less than 0.01) and of chylomicrons (Sf greater than 400; r = 0.69, P less than 0.01). No correlation was found between the fasting plasma triglyceride level and either of the plasma post-heparin lipolytic activities. Multivariate analysis revealed that 95% of the variance in triglyceride levels could be explained by the apolipoprotein B fractional synthetic rate and the chylomicron remnant clearance rate. The strong correlation between chylomicron remnant clearance, a measure of exogenous lipid metabolism, and fasting (hence, endogenous) plasma triglyceride levels suggests that remnants of chylomicrons and very low density lipoproteins share some common components of the removal process.
Cortner
J A
JA
Lipid-Heart Research Center, Children's Hospital of Philadelphia, PA 19104.
Le
N A
NA
Coates
P M
PM
Bennett
M J
MJ
Cryer
D R
DR
D000328:Adult; D001055:Apolipoproteins B / Q000378:metabolism; D002914:Chylomicrons / Q000378:metabolism; D005215:Fasting / Q000378:metabolism; D005260:Female; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D008074:Lipoproteins / Q000378:metabolism*; D008079:Lipoproteins, VLDL / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood*
D001055:Apolipoproteins B; D002914:Chylomicrons; D008074:Lipoproteins; D008079:Lipoproteins, VLDL; D014280:Triglycerides