| Blood flow and metabolic regulation in seal muscle during apnea. | |
| | |
MedLine Citation:
|
PMID: 18840667 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
In order to examine myoglobin (Mb) function and metabolic responses of seal muscle during progressive ischemia and hypoxemia, Mb saturation and high-energy phosphate levels were monitored with NMR spectroscopy during sleep apnea in elephant seals (Mirounga angustirostris). Muscle blood flow (MBF) was measured with laser-Doppler flowmetry (LDF). During six, spontaneous, 8-12 min apneas of an unrestrained juvenile seal, apneic MBF decreased to 46+/-10% of the mean eupneic MBF. By the end of apnea, MBF reached 31+/-8% of the eupneic value. The t(1/2) for 90% decline in apneic MBF was 1.9+/-1.2 min. The initial post-apneic peak in MBF occurred within 0.20+/-0.04 min after the start of eupnea. NMR measurements revealed that Mb desaturated rapidly from its eupenic resting level to a lower steady state value within 4 min after the onset of apnea at rates between 1.7+/-1.0 and 3.8+/-1.5% min(-1), which corresponded to a muscle O(2) depletion rate of 1-2.3 ml O(2) kg(-1) min(-1). High-energy phosphate levels did not change with apnea. During the transition from apnea to eupnea, Mb resaturated to 95% of its resting level within the first minute. Despite the high Mb concentration in seal muscle, experiments detected Mb diffusing with a translational diffusion coefficient of 4.5 x 10(-7) cm(2) s(-1), consistent with the value observed in rat myocardium. Equipoise P(O(2)) analysis revealed that Mb is the predominant intracellular O(2) transporter in elephant seals during eupnea and apnea. |
| | |
Authors:
|
Paul J Ponganis; Ulrike Kreutzer; Torre K Stockard; Ping-Chang Lin; Napapon Sailasuta; Tuan-Khan Tran; Ralph Hurd; Thomas Jue |
Related Documents
:
|
20963767 - Comparative determination of energy production rates and mitochondrial function using d... 12068057 - Dynamic asymmetry of phosphocreatine concentration and o(2) uptake between the on- and ... 6947247 - Mitochondrial regulation of phosphocreatine/inorganic phosphate ratios in exercising hu... 18690587 - High-energy phosphate metabolism in the exercising muscle of patients with peripheral a... 20802287 - Effects of different resistance training intensity on indices of oxidative stress. 17487077 - The influence of strain rate on the compressive stiffness properties of human lumbar in... |
Publication Detail:
|
Type: Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S. |
Journal Detail:
|
Title: The Journal of experimental biology Volume: 211 ISSN: 0022-0949 ISO Abbreviation: J. Exp. Biol. Publication Date: 2008 Oct |
Date Detail:
|
Created Date: 2008-10-08 Completed Date: 2008-12-11 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0243705 Medline TA: J Exp Biol Country: England |
Other Details:
|
Languages: eng Pagination: 3323-32 Citation Subset: IM |
Affiliation:
|
Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Cell Respiration Hemodynamics Muscles / blood supply, metabolism* Myoglobin / metabolism Oxygen / metabolism Polyphosphates / metabolism Seals, Earless / physiology* Sleep Apnea Syndromes / physiopathology, veterinary* Temperature |
| Grant Support | |
ID/Acronym/Agency:
|
GM 57355/GM/NIGMS NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Myoglobin; 0/Polyphosphates; 7782-44-7/Oxygen |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Multifocal lenses in a monochromat: the harbour seal.
Next Document: Comparison of smooth and hairy attachment pads in insects: friction, adhesion and mechanisms for dir...