title: The effect of carnitine supplementation on carnitine balance in patients with persistent post-operative infection.
abstract: The effect of L-carnitine (C) supplementation on body C balance, muscle C concentration, the leg exchange of C and some amino-acids was investigated in 8 patients with persistent post-operative infection. Before supplementation, total C concentration was 81 +/- 13 micromol/l plasma (SEM) and 15.4 +/- 1.5 micromol/g dry weight muscle, urinary excretion was 19 +/- 4 micromol/kg x 24 h and the arterial-femoral venous concentration difference over the leg (A-FV) of free C was -2.90 +/- 0.97 micromol/l, p < 0.05. Plasma-free C concentration correlated inversely with the A-FV of free C. The excretion of free C in urine was directly related to the plasma-free C concentration. A total C dose of 110 mg/kg during 4 days resulted in a 30% retention (range 12-48), a doubling of plasma C levels but no measurable alteration in either muscle C content or the arterial concentration and exchange of amino-acids over the leg. Plasma-free C concentration correlated inversely with the clearance of creatinine. In patients with persistent post-operative infection, muscle C concentration was normal and C was released from muscle as a consequence of muscle catabolism. The rate of C release was a major determinant of the plasma C concentration. At normal or low plasma C levels, the renal tubular reabsorption of C was a major determinant of body C balance. At elevated plasma concentrations of C, such as during C supplementation, the tubular capacity for reabsorption is exceeded and body carnitine balance is mainly dependent on the glomerular filtration.
authors.affiliation: Department of Anaesthesiology, Karolinska Institute, Huddinge Hospital, X-141 86 Huddinge, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Soop
authors.forename: E
authors.initials: E
authors.lastname: Forsberg
authors.forename: A
authors.initials: A
authors.lastname: Thörne
authors.forename: G
authors.initials: G
authors.lastname: Cederblad
authors.forename: J
authors.initials: J
authors.lastname: Wahren