AJP - Heart BIOPAC complete lab solutions
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 277: H683-H697, 1999;
0363-6135/99 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Arai, A. E.
Right arrow Articles by Balaban, R. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Arai, A. E.
Right arrow Articles by Balaban, R. S.
Vol. 277, Issue 2, H683-H697, August 1999

Myocardial oxygenation in vivo: optical spectroscopy of cytoplasmic myoglobin and mitochondrial cytochromes

Andrew E. Arai1, Claudia E. Kasserra1, Paul R. Territo1, Amir H. Gandjbakhche2, and Robert S. Balaban1

1 Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, and 2 Laboratory of Integrative and Medical Biophysics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892

The oxygenation state of myoglobin and the redox state of cytochrome c provide information on the PO2 in the cytosol and mitochondria, respectively. An optical "window" from ~540 to 585 nm was found in the pig heart in vivo that permitted the monitoring of myoglobin and cytochrome c without interference from Hb oxygenation or blood volume. Scanning reflectance spectroscopy was performed on the surgically exposed left ventricle of pigs. Difference spectra between control and a total left anterior descending coronary artery occlusion revealed maxima and minima in this spectral region consistent with myoglobin deoxygenation and cytochrome c and b reduction. Comparison of in vivo data with in vitro fractions of the heart, including Hb-free tissue whole heart and homogenates, mitochondria, myoglobin, and pig red blood cells, reveals minimal contributions of Hb in vivo. This conclusion was confirmed by expanding the blood volume of the myocardium and increasing mean Hb O2 saturation with an intracoronary infusion of adenosine (20 µg · kg-1 · min-1), which had no significant effect on the 540- to 585-nm region. These results also suggested that myoglobin O2 saturation was not blood flow limited under these conditions in vivo. Work jump studies with phenylephrine also failed to change cytochrome c redox state or myoglobin oxygenation. Computer simulations using recent physical data are consistent with the notion that myoglobin O2 saturation is >92% under basal conditions and does not change significantly with moderate workloads. These studies show that reflectance spectroscopy can assess myocardial oxygenation in vivo. Myoglobin O2 saturation is very high and is not labile to moderate changes in cardiac workload in the open-chest pig model. These findings indicate that myoglobin does not contribute significantly to O2 transport via facilitated diffusion under these conditions.

oxygen; mitochondria; oxygen consumption; facilitated diffusion; pig; dog; cytochrome b; cytochrome c; diffusion; computer simulation; hemoglobin


This article has been cited by other articles:


Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. Feygin, A. Mansoor, P. Eckman, C. Swingen, and J. Zhang
Functional and bioenergetic modulations in the infarct border zone following autologous mesenchymal stem cell transplantation
Am J Physiol Heart Circ Physiol, September 1, 2007; 293(3): H1772 - H1780.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
M. C. Hogan, C. M. Stary, R. S. Balaban, and C. A. Combs
NAD(P)H fluorescence imaging of mitochondrial metabolism in contracting Xenopus skeletal muscle fibers: effect of oxygen availability
J Appl Physiol, April 1, 2005; 98(4): 1420 - 1426.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
E. Takahashi and K. Asano
Mitochondrial respiratory control can compensate for intracellular O2 gradients in cardiomyocytes at low PO2
Am J Physiol Heart Circ Physiol, September 1, 2002; 283(3): H871 - H878.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
K. A. Schenkman
Cardiac performance as a function of intracellular oxygen tension in buffer-perfused hearts
Am J Physiol Heart Circ Physiol, December 1, 2001; 281(6): H2463 - H2472.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
S. French, C. Giulivi, and R. S. Balaban
Nitric oxide synthase in porcine heart mitochondria: evidence for low physiological activity
Am J Physiol Heart Circ Physiol, June 1, 2001; 280(6): H2863 - H2867.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. Zhang, K. Ugurbil, A. H. L. From, and R. J. Bache
Myocardial oxygenation and high-energy phosphate levels during graded coronary hypoperfusion
Am J Physiol Heart Circ Physiol, January 1, 2001; 280(1): H318 - H326.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
A. H. Gandjbakhche, R. F. Bonner, A. E. Arai, and R. S. Balaban
Visible-light photon migration through myocardium in vivo
Am J Physiol Heart Circ Physiol, August 1, 1999; 277(2): H698 - H704.
[Abstract] [Full Text] [PDF]

Home page
 Proc. Natl. Acad. Sci. USAHome page
S. Papadopoulos, V. Endeward, B. Revesz-Walker, K. D. Jurgens, and G. Gros
Radial and longitudinal diffusion of myoglobin in single living heart and skeletal muscle cells
PNAS, May 8, 2001; 98(10): 5904 - 5909.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online