In vivo kinetics of atherogenic remnant lipoprotiens

1998 Fiscal Year Final Research Report Summary

• Project/Area Number: 09671074
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 内分泌・代謝学
• Research Institution: JIKEI UNIVERSITY SCHOOL of MEDICINE
• Principal Investigator: NISHIDE Ryouichi JIKEI UNIVERSITY SCHOOL of MEDICINE,instructor, 医学部, 助手 (30266663)
• Co-Investigator(Kenkyū-buntansha): IKEWAKI Katsunori JIKEI UNIVERSITY SCHOOL of MEDICINE,LECTURER, 医学部, 講師 (40287199)
• Project Period (FY): 1997 – 1998
• Keywords: remnant / kinetics / tracer / stable isotope / GC-MS / fractional catabolic rate / production rate / compartmental model

Research Abstract

Remnants (chylomicron remnant, VLDL remnant) have been considered to be proatherogenic. However, their exact in vivo metabolism remains unclear. In this study, we performed in vivo kinetic studies using a new labeling technique, namely stable isotopically labeled amino acid method, in type III dyslipidemic patients. D3-Leucine was infused for 12 hours and blood samples were collected frequently during infusion period and followed up to 72 hours. VLDL, IDL, and LDL were isolated by sequential ultracentrifugation and each fraction was further subfractionated into remnant and non-remnant fractions using monoclonal anti-apoB100 antibody. ApoB-100 was isolated by SDSPAGE, followed by hydrolysis and cation exchange chromatography. Tracer/tracee ratio was determined by gas-chromatograph mass-s pectrometry. Tracer/tracee ratios were integrated into multicompartmental model to determine kinetic papameters. As the results, kinetic parameters were not different between remnant and non-remnant fractions. Based on the resuls obtained, remnants are metabolically indistinct from non-remnants in type III patients.