Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
5
|
| pubmed:dateCreated |
1993-6-15
|
| pubmed:abstractText |
To test whether carnitine availability is rate-limiting for fat oxidation under conditions of augmented oxidative use of fatty substrates, two series of studies were performed. In study no. 1, L-carnitine (1 g + 0.5 g/h intravenously [i.v.]) or saline was given to eight volunteers during a 4-hour infusion of a 10% triglyceride emulsion, thereby increasing plasma free-carnitine levels from 38 +/- 4 to 415 +/- 55 mumol/L. Fat infusion increased plasma triglyceride levels (80%) and lipid oxidation (30%), and decreased (28%) carbohydrate oxidation (as measured by indirect calorimetry); hypercarnitinemia had no influence on these responses. In study no. 2 in 12 healthy subjects a bolus of L-carnitine (3 g) or saline was administered 40 minutes before aerobic exercise (bicycling for 40 minutes at 60 W), followed by 2 minutes of anaerobic exercise (250 W) and 50 minutes of recovery. Oxygen consumption (VO2), increased to 18.3 +/- 0.7 mL.min-1 x kg-1 during aerobic exercise, reached a maximum of 46.0 +/- 0.8 mL.min-1 x kg-1 during the anaerobic bout, and returned to baseline within a few minutes, with no difference between control and carnitine. At virtually identical mean energy expenditure rates (196 +/- 7 v 197 +/- 7 J.min-1 x kg-1, saline v carnitine), after carnitine administration the entire exercise protocol was sustained by a lower mean carbohydrate oxidation rate (42.1 +/- 3.6 v 36.5 +/- 2.3 mumol.min-1 x kg-1, P < .03) and a higher mean lipid oxidation rate (6.7 +/- 1.0 v 8.3 +/- 0.7 mumol.min-1 x kg-1, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
May
|
| pubmed:issn |
0026-0495
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
42
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
594-600
|
| pubmed:dateRevised |
2005-11-17
|
| pubmed:meshHeading |
pubmed-meshheading:8492714-Adult,
pubmed-meshheading:8492714-Blood,
pubmed-meshheading:8492714-Carnitine,
pubmed-meshheading:8492714-Fat Emulsions, Intravenous,
pubmed-meshheading:8492714-Heart Rate,
pubmed-meshheading:8492714-Humans,
pubmed-meshheading:8492714-Infusions, Intravenous,
pubmed-meshheading:8492714-Lipid Metabolism,
pubmed-meshheading:8492714-Male,
pubmed-meshheading:8492714-Oxidation-Reduction,
pubmed-meshheading:8492714-Pulmonary Gas Exchange,
pubmed-meshheading:8492714-Time Factors
|
| pubmed:year |
1993
|
| pubmed:articleTitle |
Effects of acute hypercarnitinemia during increased fatty substrate oxidation in man.
|
| pubmed:affiliation |
Metabolism Unit, C.N.R. (Consiglio Nazionale delle Ricerche) Institute of Clinical Physiology, Pisa, Italy.
|
| pubmed:publicationType |
Journal Article
|