title: Elimination rate of fat emulsion particles from plasma in Japanese subjects as determined by a triglyceride clamp technique.
abstract: The elimination rate of emulsion triglyceride (TG) from plasma was investigated in Japanese subjects by a plasma TG clamp technique. Two different studies were performed. In Study 1, a lipid emulsion (20% long-chain triglyceride emulsion: LCT) was infused into a healthy research associate to achieve a certain concentration of TG in the plasma. Thereafter, the infusion rate was adjusted to maintain the chosen concentrations of TG in plasma (namely, 4-5 mmol/L, 3-4 mmol/L, and approximately 2 mmol/L) over a period of 160 min by measuring plasma TG concentrations at 10-min intervals. Concentrations of TG in plasma were clamped within 2.13 +/- 0.13 mmol/L by an infusion rate of 0.10 g.kg-1.h-1, within 3.34 +/- 0.20 mmol/L by an infusion rate of 0.14 g.kg-1.h-1, and within 4.46 +/- 0.22 mmol/L by an infusion rate of 0.11 g.kg-1.h-1. The mean rate of infusion of emulsified TG that had maintained the steady concentrations of TG in plasma was limited to the very narrow range of 0.12 +/- 0.02 g of TG.kg-1.h-1 regardless of the chosen concentration of TG in plasma. Concentrations of nonesterified fatty acids (NEFA) also remained at a fixed level of 1.378 +/- 0.103 mEq/L regardless of the chosen concentration of TG in the plasma. Study 2 was undertaken to determine whether plasma TG concentration reached a plateau during a period when emulsion TG was infused into three different subjects at a rate of 0.12 g.kg-1.h-1. The plasma TG concentrations were steady at a level of 2.04 +/- 0.32 mmol/L, and the plasma NEFA concentrations remained at a fixed level of 1.33 +/- 0.13 mEq/L, over a period of 160 min after 50-min priming infusion. These results indicate that the plasma TG elimination rate was limited to the narrow range of 0.12 +/- 0.02 g.kg-1.h-1 when the fat emulsion was infused into Japanese subjects in a steady state. However, the plasma TG elimination rate in Japanese subjects appeared to be lower than that of Europeans. This may be due to a difference in lipoprotein lipase activity caused by different dietary habits, namely, a lower fat intake.
authors.affiliation: Second Department of Surgery, Mie University School of Medicine, Tsu, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Iriyama
authors.forename: T
authors.initials: T
authors.lastname: Tsuchibashi
authors.forename: C
authors.initials: C
authors.lastname: Miki
authors.forename: I
authors.initials: I
authors.lastname: Kalembeyi
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: H
authors.initials: H
authors.lastname: Urata
authors.forename: R
authors.initials: R
authors.lastname: Saitoh
mesh_terms: D000328:Adult; D005217:Fat Emulsions, Intravenous / Q000493:pharmacokinetics*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D015309:Glucose Clamp Technique; D006801:Humans; D007564:Japan; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood*
chemical_list: D005217:Fat Emulsions, Intravenous; D005230:Fatty Acids, Nonesterified; D014280:Triglycerides