This study was conducted to investigate developmental changes in the kinetics of carnitine palmitoyltransferase (CPT) within hepatic and skeletal muscle tissues of the canine species. Carnitine concentrations, CPT activity and the apparent K(m) for carnitine were measured in tissue homogenates from dogs in six age categories: newborn; 24-h-old; 3-, 6- and 9-wk-old; and adult. Hepatic CPT activi...

Four experiments were conducted to evaluate the effects of supplementing graded levels (0 to 100 ppm) of L-carnitine to the diet of weanling pigs on growth performance during a 34- to 38-d experimental period. A fifth experiment was conducted to determine the effects of addition of L-carnitine to diets with or without added soybean oil (SBO) on growth performance. In Exp. 1, 128 pigs (initial B...

Introduction: In order to clarify the characteristics of different administration routes and to optimize the dosage, carnitine kinetics was investigated under oral and intravenous supplementation. Methods: Lcarnitine was administered orally (900mg) for 12months, intravenously (1000 mg) for 3months and (500mg) for 3months sequentially in 18 chronic hemodialysis patients. Plasma free and acyl car...

The naturally occurring compatible solutes betaine and L-carnitine allow the food-borne pathogen Listeria monocytogenes to adjust to environments of high osmotic strength. Previously, it was demonstrated that L. monocytogenes possesses an ATP-dependent L-carnitine transporter (A. Verheul, F. M. Rombouts, R. R. Beumer, and T. Abee, J. Bacteriol. 177:3205-3212, 1995). The present study reveals th...

Carnitine metabolism has been previously shown to change with exercise in normal subjects, and in patients with ischemic muscle diseases. To characterize carnitine metabolism further during exercise, six normal male subjects performed constant-load exercise on a bicycle ergometer on two separate occasions. Low-intensity exercise was performed for 60 min at a work load equal to 50% of the lactat...

There are many causes for carnitine depletion during maintenance hemodialysis. Supplementation with L-carnitine in animals has been associated with improvement in some abnormalities also present in chronic renal failure. However, it is still controversial whether restoring plasma or tissue carnitine will correct clinical or biologic symptoms observed in maintenance hemodialysis. A systematic re...

OBJECTIVE Carnitine homeostasis is disrupted in lambs with endothelial dysfunction secondary to increased pulmonary blood flow (Shunt). Our recent studies have also indicated that the disruption in carnitine homeostasis correlates with a decrease in PPAR-γ expression in Shunt lambs. Thus, this study was carried out to determine if there is a causal link between loss of PPAR-γ signaling and carn...

Three experiments using 1,356 pigs (C22 × 336 PIC) were conducted to determine the interactive effects of dietary L-carnitine and ractopamine hydrochloride (RAC) on carcass characteristics and meat quality of finishing pigs. Experiments were arranged as factorials with main effects of L-carnitine and RAC; L-carnitine levels were 0, 25, or 50 mg/kg in Exp. 1 and 2 and 0 or 50 mg/kg in Exp. 3, an...

New knowledge on the physiologic role of L-carnitine and on the rationale of its use in patients on maintenance hemodialysis is provided. In particular, carnitine normalizes plasma and muscle carnitine levels and modifies both enzymatic pattern of muscle and morphology of single fibers, improving exercise tolerance. In addition, carnitine reduces erythropoietin requirements, the number of hypot...

The distribution of acetyl coenzyme A-carnitine acetyltransferase (EC 2.3.1.7) and of palmityl-CoA-carnitine palmityltransferase (EC 2.3.1) in subcellular fractions of rat liver has been studied. The distribution of carnitine pahnityltransferase in the different fractions obtained with differential centrifugation and with centrifugation in a steep sucrose gradient correlated closely with the di...