| Increased myocardial lactate oxidation in lambs with aortopulmonary shunts at rest and during exercise. | |
| | |
MedLine Citation:
|
PMID: 9815054 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Free fatty acids are the major fuels for the myocardium, but during a higher load carbohydrates are preferred. Previously, we demonstrated that myocardial net lactate uptake was higher in lambs with aortopulmonary shunts than in control lambs. To determine whether this was caused by an increased lactate uptake and oxidation or by a decreased lactate release, we studied myocardial lactate and glucose metabolism with 13C-labeled substrates in 36 lambs in a fasting, conscious state. The lambs were assigned to two groups: a resting group consisting of 8 shunt and 9 control lambs, and an exercise group (50% of peak O2 consumption) consisting of 9 shunt and 10 control lambs. Myocardial lactate oxidation was higher in shunt than in control lambs (mean +/- SE, rest: 10.33 +/- 2.61 vs. 0. 17 +/- 0.82, exercise: 38.05 +/- 8.87 vs. 16.89 +/- 4.78 micromol. min-1. 100 g-1; P < 0.05). There was no difference in myocardial lactate release between shunt and control lambs. Oxidation of exogenous glucose, which was approximately zero at rest, increased during exercise in shunt and control lambs. The contribution of glucose and lactate to myocardial oxidative metabolism increased during exercise compared with at rest in both shunt and control lambs. We conclude that myocardial lactate oxidation is higher in shunt than in control lambs, both at rest and during exercise, and that the contribution of carbohydrates in myocardial oxidative metabolism in shunt lambs is higher than in control lambs. Thus it appears that this higher contribution of carbohydrates occurs not only in the case of pressure-overloaded hearts but also in myocardial hypertrophy due to volume overloading. |
| | |
Authors:
|
G C Beaufort-Krol; J Takens; M C Molenkamp; G B Smid; K J Meuzelaar; W G Zijlstra; J R Kuipers |
Related Documents
:
|
1642734 - Effect of dca administration or endurance training on lactate metabolism in mice during... 2038174 - Muscle metabolism and red cell atp/adp concentration during bicycle ergometer in patien... 16195984 - Critical swimming speed does not represent the speed at maximal lactate steady state. 1688914 - Haemodilution with medium molecular weight hydroxyethyl starch in patients with periphe... 8769754 - Developmental changes in atp utilization during graded hypoxia and reoxygenation in the... 8305914 - Effect of carbohydrate composition on fluid balance, gastric emptying, and exercise per... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: The American journal of physiology Volume: 275 ISSN: 0002-9513 ISO Abbreviation: Am. J. Physiol. Publication Date: 1998 Nov |
Date Detail:
|
Created Date: 1998-12-10 Completed Date: 1998-12-10 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 0370511 Medline TA: Am J Physiol Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: H1503-12 Citation Subset: IM |
Affiliation:
|
Division of Pediatric Cardiology and Thoracic Surgery, Beatrix Children's Hospital, University of Groningen, 9700 RB Groningen, The Netherlands. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Arteriovenous Shunt, Surgical* Coronary Vessels / metabolism, surgery Glucose / metabolism Lactic Acid / metabolism* Myocardium / metabolism* Oxidation-Reduction Physical Conditioning, Animal* Sheep |
| Chemical | |
Reg. No./Substance:
|
50-21-5/Lactic Acid; 50-99-7/Glucose |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Effect of gastrin on antroduodenal motility: role of intraluminal acidity.
Next Document: Ventricular contractility in atrial fibrillation is predictable by mechanical restitution and potent...