Linked Life Data

2228867

Source:http://linkedlifedata.com/resource/pubmed/id/2228867

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-12-5
pubmed:abstractText
We investigated the relationships among maximal O2 uptake (VO2max), effluent venous PO2 (PvO2), and calculated mean capillary PO2 (PCO2) in isolated dog gastrocnemius in situ as arterial PO2 (PaO2) was progressively reduced with muscle blood flow held constant. The hypothesis that VO2max is determined in part by peripheral tissue O2 diffusion predicts proportional declines in VO2max and PCO2 if the diffusing capacity of the muscle remains constant. The inspired O2 fraction was altered in each of six dogs to produce four different levels of PaO2 [22 +/- 2, 29 +/- 1, 38 +/- 1, and 79 +/- 4 (SE) Torr]. Muscle blood flow, with the circulation isolated, was held constant at 122 +/- 15 ml.100 g-1.min-1 while the muscle worked maximally (isometric twitches at 5-7 Hz) at each of the four different values of PaO2. Arterial and venous samples were taken to measure lactate, pH, PO2, PCO2, and muscle VO2. PCO2 was calculated using Fick's law of diffusion and a Bohr integration procedure. VO2max fell progressively (P less than 0.01) with decreasing PaO2. The decline in VO2max was proportional (R = 0.99) to the fall in both muscle PvO2 and calculated PCO2 while the calculated muscle diffusing capacity was not different among the four conditions. Fatigue developed more rapidly with lower PaO2, although lactate output from the muscle was not different among conditions. These results are consistent with the hypothesis that resistance to O2 diffusion in the peripheral tissue may be a principal determinant of VO2max.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
570-6
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Maximal O2 uptake of in situ dog muscle during acute hypoxemia with constant perfusion.
pubmed:affiliation
Department of Medicine, University of California, San Diego, La Jolla 92093.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.