AJP - Heart Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 282: H508-H515, 2002. First published October 11, 2001; doi:10.1152/ajpheart.00722.2001
0363-6135/02 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
282/2/H508    most recent
00722.2001v1
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 ISI Web of Science
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 ISI Web of Science (4)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Takamura, M.
Right arrow Articles by Lavallée, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Takamura, M.
Right arrow Articles by Lavallée, M.
Vol. 282, Issue 2, H508-H515, February 2002

Enhanced contribution of NO to exercise-induced coronary responses after alpha -adrenergic receptor blockade

Masayuki Takamura, Robert Parent, and Michel Lavallée

Department of Physiology, Faculty of Medicine, Université de Montréal, and Institut de Cardiologie de Montréal, Montréal, Québec, Canada H1T 1C8

We hypothesized that nitric oxide (NO), in addition to beta -adrenergic effects, may contribute to exercise-induced coronary responses after alpha -adrenergic receptor blockade. Data were analyzed as relationships between coronary sinus (CS) O2 saturation (CS O2sat) or coronary blood flow (CBF) and myocardial O2 consumption (MVO2). As MVO2 increased, CS O2sat fell more (P < 0.05) after Nomega -nitro-L-arginine methyl ester (L-NAME; slope = -2.9 ± 0.4 × 10-2 %saturation · µl O2 · min-1 · g-1) than before (slope = -2.1 ± 0.3 × 10-2 %saturation · µl O2 · min-1 · g-1). The slope of CBF versus MVO2 was not altered. After blockade of alpha -adrenergic receptors alone (phentolamine), CS O2sat failed to decrease as MVO2 increased (slope = -0.1 ± 0.5 × 10-2 %saturation · µl O2 · min-1 · g-1). L-NAME given after phentolamine led to substantial decreases in CS O2sat (P < 0.01) as MVO2 increased (slope = -2.1 ± 0.4 × 10-2 percent saturation · µl O2-1 · min-1 · g-1). CBF responses to exercise were smaller (P < 0.01) after phentolamine + L-NAME (slope = 6.1 ± 0.1 × 10-3 ml/µl O2) than after phentolamine alone (slope = 6.9 ± 0.2 × 10-3 ml/µl O2). Thus a significant portion of exercise-induced coronary responses after alpha -adrenergic receptor blockade involves NO formation.

endothelium; metabolism; oxygen; adrenergic receptors; coronary sinus


This article has been cited by other articles:


Home page
 DiabetesHome page
M. M. Madsen, H. M. Sondergaard, M. Bottcher, N. H. Buus, O. Schmitz, H. E. Botker, and T. T. Nielsen
Impact of Type 2 Diabetes on Nitric Oxide and Adrenergic Modulation of Myocardial Perfusion
Diabetes, February 1, 2007; 56(2): 468 - 475.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
J. D. Tune, M. W. Gorman, and E. O. Feigl
Matching coronary blood flow to myocardial oxygen consumption
J Appl Physiol, July 1, 2004; 97(1): 404 - 415.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
S. Setty, W. Sun, R. Martinez, H. F. Downey, and J. D. Tune
{alpha}-Adrenoceptor-mediated coronary vasoconstriction is augmented during exercise in experimental diabetes mellitus
J Appl Physiol, July 1, 2004; 97(1): 431 - 438.
[Abstract] [Full Text] [PDF]

Home page
 Exp. Biol. Med.Home page
P. Zong, W. Sun, S. Setty, J. D. Tune, and H. F. Downey
{alpha}-Adrenergic Vasoconstrictor Tone Limits Right Coronary Blood Flow in Exercising Dogs
Experimental Biology and Medicine, April 1, 2004; 229(4): 312 - 322.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
M. Okajima, M. Takamura, P. Vequaud, R. Parent, and M. Lavallee
beta -Adrenergic receptor blockade impairs NO-dependent dilation of large coronary arteries during exercise
Am J Physiol Heart Circ Physiol, February 1, 2003; 284(2): H501 - H510.
[Abstract] [Full Text] [PDF]


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