AJP - Heart Calcium Transients and Cell-Sarcomere
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 281: H738-H744, 2001;
0363-6135/01 $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 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 Web of Science (7)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chen, Y.
Right arrow Articles by Bache, R. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chen, Y.
Right arrow Articles by Bache, R. J.
Vol. 281, Issue 2, H738-H744, August 2001

Selective blockade of mitochondrial KATP channels does not impair myocardial oxygen consumption

Yingjie Chen, Jay H. Traverse, Jianyi Zhang, and Robert J. Bache

Departments of Medicine and Radiology, University of Minnesota, Minneapolis, Minnesota 55455

Opening of mitochondrial ATP-sensitive potassium (KATP) channels has been postulated to prevent inhibition of respiration resulting from matrix contraction during high rates of ATP synthesis. Glibenclamide, which blocks KATP channels on the sarcolemma of vascular smooth muscle cells and myocardial myocytes as well as on the inner mitochondrial membrane, results in a decrease of myocardial oxygen consumption (MVO2) both at rest and during exercise. This study examined whether this represents a primary effect of blockade of mitochondrial KATP channels or occurs secondary to coronary resistance vessel constriction with a decrease of coronary blood flow (CBF) and myocardial oxygen availability. MVO2 was measured at rest and during treadmill exercise in 10 dogs during control conditions, after selective mitochondrial KATP channel blockade with 5-hydroxydecanoate (5-HD), and after nonselective KATP channel blockade with glibenclamide. During control conditions, exercise resulted in progressive increases of CBF and MVO2. Glibenclamide (50 µg · kg-1 · min-1 ic) resulted in a 17 ± 6% decrease of resting CBF with a downward shift of CBF during exercise and a decrease of coronary venous PO2, indicating increased myocardial oxygen extraction. In contrast with the effects of glibenclamide, 5-HD (0.7 mg · kg-1 · min-1 ic) had no effect on CBF, MVO2, or myocardial oxygen extraction. These findings suggest that glibenclamide decreased MVO2 by causing resistance vessel constriction with a decrease of CBF and oxygen available to the myocardium rather than to a primary reduction of mitochondrial respiration.

glibenclamide; 5-hydroxydecanoate; exercise; coronary blood flow


This article has been cited by other articles:


Home page
 Arterioscler. Thromb. Vasc. Bio.Home page
H. M. O. Farouque, S. G. Worthley, and I. T. Meredith
Effect of ATP-Sensitive Potassium Channel Inhibition on Coronary Metabolic Vasodilation in Humans
Arterioscler Thromb Vasc Biol, May 1, 2004; 24(5): 905 - 910.
[Abstract] [Full Text]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. Zhang, A. H. L. From, K. Ugurbil, and R. J. Bache
Myocardial oxygenation and high-energy phosphate levels during KATP channel blockade
Am J Physiol Heart Circ Physiol, October 1, 2003; 285(4): H1420 - H1427.
[Abstract] [Full Text] [PDF]

Home page
 Circ. Res.Home page
H. M. O. Farouque, S. G. Worthley, I. T. Meredith, R. A. P. Skyrme-Jones, and M. J. Zhang
Effect of ATP-Sensitive Potassium Channel Inhibition on Resting Coronary Vascular Responses in Humans
Circ. Res., February 8, 2002; 90(2): 231 - 236.
[Abstract] [Full Text] [PDF]

Home page
 Circ. Res.Home page
H. M. O. Farouque, S. G. Worthley, I. T. Meredith, R. A. P. Skyrme-Jones, and M. J. Zhang
Effect of ATP-Sensitive Potassium Channel Inhibition on Resting Coronary Vascular Responses in Humans
Circ. Res., February 8, 2002; 90(2): 231 - 236.
[Abstract] [Full Text] [PDF]


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