Carnitine supplementation and fat emulsion clearance and utilization.
The aim of the present work is to learn if intravenous administration of L-carnitine accelerates the clearance of a lipid emulsion. Intravenous fat tolerance tests have been done on rats (0.4 g triacylglycerols.kg-1 B.W.). Measurement of the light scattering index of the plasma permitted determination of the exogenous lipid concentration and thus allowed to represent the clearance curve of the infused emulsion. It was found that prior administration of L-carnitine (110, 160 or 560 mg.kg-1 B.W.) does not modify the clearance rate either of a long chain triglyceride emulsion or of a medium chain triglyceride based emulsion. The observed clearance in L-carnitine deficient animals, resulting either from intraperitoneal injections of D-carnitine (3 g.kg-1 B.W. for four days) or from a 6-months long diet of suboptimal amounts of precursor amino acids and vitamins for carnitine biosynthesis, was not reduced relative to the clearance in corresponding control animals. Also, the in vitro activities of the two enzymes involved in the clearance of the infused lipids, lipoprotein lipase (diaphragm and adipose tissue) and hepatic endothelial lipase, were unmodified by the L-carnitine.
Lave
T
T
Laboratoire, Clinique Médicale A, Hôpital Civil, Strasbourg, France.
Lutz
O
O
Frey
A
A
Ehret
C
C
Bach
A C
AC
D000818:Animals; D002331:Carnitine / Q000008:administration & dosage* / Q000172:deficiency; D005217:Fat Emulsions, Intravenous / Q000493:pharmacokinetics*; D007262:Infusions, Intravenous; D008071:Lipoprotein Lipase / Q000097:blood; D008099:Liver / Q000201:enzymology; D008297:Male; D008657:Metabolic Clearance Rate; D051381:Rats; D011919:Rats, Inbred Strains
D005217:Fat Emulsions, Intravenous; D008071:Lipoprotein Lipase; D002331:Carnitine