| Metabolic and cardiorespiratory responses to "the lactate clamp". | |
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MedLine Citation:
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PMID: 12376315 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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To evaluate the hypothesis that precursor supply limits gluconeogenesis (GNG) during exercise, we examined training-induced changes in glucose kinetics [rates of appearance (R(a)) and disappearance (R(d))], oxidation (R(ox)), and recycling (R(r)) with an exogenous lactate infusion to 3.5-4.0 mM during rest and to pretraining 65% peak O(2) consumption (VO(2 peak)) levels during exercise. Control and clamped trials (LC) were performed at rest pre- (P(R)R, P(R)R-LC) and posttraining (P(O)R, P(O)R-LC) and during exercise pre- (P(R)E(X)) and posttraining at absolute (P(O)A(B), P(O)A(B)-LC) and relative (P(O)R(L), P(O)R(L)-LC) intensities. Glucose R(r) was not different in any rest or exercise condition. Glucose R(a) did not differ as a result of LC. Glucose R(ox) was significantly decreased with LC at P(O)R (0.38 +/- 0.03 vs. 0.56 +/- 0.04 mg. kg(-1). min(-1)) and P(O)A(B) (3.82 +/- 0.51 vs. 5.0 +/- 0.62 mg. kg(-1). min(-1)). Percent glucose R(d) oxidized decreased with all LC except P(O)R(L)-LC (P(R)R, 32%; P(R)R-LC, 22%; P(O)R, 27%; P(O)R-LC, 20%; P(O)A(B), 95%; P(O)A(B)-LC, 77%), which resulted in a significant increase in oxidation from alternative carbohydrate (CHO) sources at rest and P(O)A(B). We conclude that 1) increased arterial [lactate] did not increase glucose R(r) measured during rest or exercise after training, 2) glucose disposal or production did not change with increased precursor supply, and 3) infusion of exogenous CHO in the form of lactate resulted in the decrease of glucose R(ox). |
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Authors:
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Benjamin F Miller; Jill A Fattor; Kevin A Jacobs; Michael A Horning; Sang-Hoon Suh; Franco Navazio; George A Brooks |
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Publication Detail:
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Type: Clinical Trial; Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: American journal of physiology. Endocrinology and metabolism Volume: 283 ISSN: 0193-1849 ISO Abbreviation: Am. J. Physiol. Endocrinol. Metab. Publication Date: 2002 Nov |
Date Detail:
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Created Date: 2002-10-11 Completed Date: 2002-11-08 Revised Date: 2008-11-21 |
Medline Journal Info:
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Nlm Unique ID: 100901226 Medline TA: Am J Physiol Endocrinol Metab Country: United States |
Other Details:
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Languages: eng Pagination: E889-98 Citation Subset: IM |
Affiliation:
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Department of Integrative Biology, University of California, Berkeley, California 94720, USA. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Adolescent Adult Blood Glucose / metabolism* Blood Pressure / drug effects, physiology* Energy Metabolism / drug effects, physiology Fatty Acids, Nonesterified / blood Glycerol / blood Heart Rate / drug effects, physiology* Homeostasis / drug effects, physiology Humans Insulin / blood Lactic Acid / blood, pharmacokinetics* Male Oxygen Consumption / physiology Physical Exertion / drug effects, physiology* Respiration Rest / physiology Weight Loss / physiology |
| Grant Support | |
ID/Acronym/Agency:
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AR-42906/AR/NIAMS NIH HHS |
| Chemical | |
Reg. No./Substance:
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0/Blood Glucose; 0/Fatty Acids, Nonesterified; 11061-68-0/Insulin; 50-21-5/Lactic Acid; 56-81-5/Glycerol |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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