Significance of measuring serum concentrations of remnant lipoproteins and apolipoprotein B-48 in fasting period.

Aim: To characterize lipid profiles conveniently in the fasting period to detect postprandial hyperlipidemic subjects, we measured the concentrations of lipids, including remnant lipoproteins and apoB-48, before and after loading the test meal in 24 normolipidemic subjects.

Methods: We examined remnant-like particle-cholesterol and -triglyceride (RLP-C, RLP-TG) by the immune adsorption method, RemL-C by the newly developed homogeneous method, and apoB-48 by chemiluminescence enzyme immunoassay.

Results: After loading, TG, RemL-C, RLP-C, RLP-TG, and apoB-48 concentrations were elevated. Twenty subjects had only a slight elevation of TG (low TG group) after loading, while 4 subjects showed apparent increase of TG (more than 150 mg/dL, high TG group). In the fasting period, the high TG group had significantly higher serum concentrations of TG and RemL-C than the low TG group. Although not significant, RLP-C, RLP-TG and apoB-48 concentrations in the high TG group were also higher than in the low TG group. After loading, serum concentrations of TG, RemL-C, RLP-C, RLP-TG, and apoB-48 increased significantly more in the high TG group than in the low TG group.

Conclusion: In conclusion, TG, RemL-C, RLP-C, RLP-TG, and apoB-48 concentrations in the fasting period may be suitable for detecting postprandial hyperlipidemic subjects.