Role of ATP-sensitive potassium channels in coronary microvascular autoregulatory responses

T. Komaru, K. G. Lamping, C. L. Eastham, Kevin C Dellsperger

Research output: Contribution to journalArticle

106 Citations (Scopus)

Abstract

The purpose of the present study was to test the hypothesis that ATP-sensitive potassium channels mediate autoregulatory vasodilatation of coronary arterioles in vivo. Experiments were performed in 23 open-chest anesthetized dogs. Coronary arterial microvascular diameters were directly measured with fluorescence microangiography using an intravital microscope and stroboscopic epi-illumination synchronized to the cardiac cycle. A mild coronary stenosis (perfusion pressure=60 mm Hg), a critical coronary stenosis (perfusion pressure=40 mm Hg), and complete coronary artery occlusion were produced with an occluder around the left anterior descending coronary artery in the presence or absence of glibenclamide (10-5 M, topically), which inhibits ATP-sensitive potassium channels, or of vehicle. During topical application of vehicle (0.01% dimethyl sulfoxide), there was dilatation of small (<100 μm diameter) arterioles during reductions in perfusion pressure (percent change in diameter: 6.7±1.5%, 11.7±3.5%, and 10.4±5.1% during mild stenosis, critical stenosis, and complete occlusion, respectively). In the presence of glibenclamide, arteriolar dilatations during coronary stenoses and occlusions were abolished. Glibenclamide did not affect responses of arterioles > 100 μm. Glibenclamide did not alter microvascular responses to nitroprusside. These data suggest that ATP-sensitive potassium channels play an important role in determining the coronary microvascular response to reductions in perfusion pressure.

Original languageEnglish (US)
Pages (from-to)1146-1151
Number of pages6
JournalCirculation research
Volume69
Issue number4
DOIs
StatePublished - Jan 1 1991

Fingerprint

KATP Channels
Perfusion
Glyburide
Coronary Stenosis
Pressure
Coronary Vessels
Coronary Occlusion
Arterioles
Nitroprusside
Dimethyl Sulfoxide
Lighting
Vasodilation
Dilatation
Thorax
Fluorescence
Dogs

Keywords

  • Autoregulation
  • Coronary arterioles
  • Glibenclamide
  • Intravital microscopy
  • Ischemia
  • Microcirculation

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine

Cite this

Role of ATP-sensitive potassium channels in coronary microvascular autoregulatory responses. / Komaru, T.; Lamping, K. G.; Eastham, C. L.; Dellsperger, Kevin C.

In: Circulation research, Vol. 69, No. 4, 01.01.1991, p. 1146-1151.

Research output: Contribution to journalArticle

Komaru, T. ; Lamping, K. G. ; Eastham, C. L. ; Dellsperger, Kevin C. / Role of ATP-sensitive potassium channels in coronary microvascular autoregulatory responses. In: Circulation research. 1991 ; Vol. 69, No. 4. pp. 1146-1151.
@article{1f498788bf464ff990f4f0dc8baf638a,
title = "Role of ATP-sensitive potassium channels in coronary microvascular autoregulatory responses",
abstract = "The purpose of the present study was to test the hypothesis that ATP-sensitive potassium channels mediate autoregulatory vasodilatation of coronary arterioles in vivo. Experiments were performed in 23 open-chest anesthetized dogs. Coronary arterial microvascular diameters were directly measured with fluorescence microangiography using an intravital microscope and stroboscopic epi-illumination synchronized to the cardiac cycle. A mild coronary stenosis (perfusion pressure=60 mm Hg), a critical coronary stenosis (perfusion pressure=40 mm Hg), and complete coronary artery occlusion were produced with an occluder around the left anterior descending coronary artery in the presence or absence of glibenclamide (10-5 M, topically), which inhibits ATP-sensitive potassium channels, or of vehicle. During topical application of vehicle (0.01{\%} dimethyl sulfoxide), there was dilatation of small (<100 μm diameter) arterioles during reductions in perfusion pressure (percent change in diameter: 6.7±1.5{\%}, 11.7±3.5{\%}, and 10.4±5.1{\%} during mild stenosis, critical stenosis, and complete occlusion, respectively). In the presence of glibenclamide, arteriolar dilatations during coronary stenoses and occlusions were abolished. Glibenclamide did not affect responses of arterioles > 100 μm. Glibenclamide did not alter microvascular responses to nitroprusside. These data suggest that ATP-sensitive potassium channels play an important role in determining the coronary microvascular response to reductions in perfusion pressure.",
keywords = "Autoregulation, Coronary arterioles, Glibenclamide, Intravital microscopy, Ischemia, Microcirculation",
author = "T. Komaru and Lamping, {K. G.} and Eastham, {C. L.} and Dellsperger, {Kevin C}",
year = "1991",
month = "1",
day = "1",
doi = "10.1161/01.RES.69.4.1146",
language = "English (US)",
volume = "69",
pages = "1146--1151",
journal = "Circulation Research",
issn = "0009-7330",
publisher = "Lippincott Williams and Wilkins",
number = "4",

}

TY - JOUR

T1 - Role of ATP-sensitive potassium channels in coronary microvascular autoregulatory responses

AU - Komaru, T.

AU - Lamping, K. G.

AU - Eastham, C. L.

AU - Dellsperger, Kevin C

PY - 1991/1/1

Y1 - 1991/1/1

N2 - The purpose of the present study was to test the hypothesis that ATP-sensitive potassium channels mediate autoregulatory vasodilatation of coronary arterioles in vivo. Experiments were performed in 23 open-chest anesthetized dogs. Coronary arterial microvascular diameters were directly measured with fluorescence microangiography using an intravital microscope and stroboscopic epi-illumination synchronized to the cardiac cycle. A mild coronary stenosis (perfusion pressure=60 mm Hg), a critical coronary stenosis (perfusion pressure=40 mm Hg), and complete coronary artery occlusion were produced with an occluder around the left anterior descending coronary artery in the presence or absence of glibenclamide (10-5 M, topically), which inhibits ATP-sensitive potassium channels, or of vehicle. During topical application of vehicle (0.01% dimethyl sulfoxide), there was dilatation of small (<100 μm diameter) arterioles during reductions in perfusion pressure (percent change in diameter: 6.7±1.5%, 11.7±3.5%, and 10.4±5.1% during mild stenosis, critical stenosis, and complete occlusion, respectively). In the presence of glibenclamide, arteriolar dilatations during coronary stenoses and occlusions were abolished. Glibenclamide did not affect responses of arterioles > 100 μm. Glibenclamide did not alter microvascular responses to nitroprusside. These data suggest that ATP-sensitive potassium channels play an important role in determining the coronary microvascular response to reductions in perfusion pressure.

AB - The purpose of the present study was to test the hypothesis that ATP-sensitive potassium channels mediate autoregulatory vasodilatation of coronary arterioles in vivo. Experiments were performed in 23 open-chest anesthetized dogs. Coronary arterial microvascular diameters were directly measured with fluorescence microangiography using an intravital microscope and stroboscopic epi-illumination synchronized to the cardiac cycle. A mild coronary stenosis (perfusion pressure=60 mm Hg), a critical coronary stenosis (perfusion pressure=40 mm Hg), and complete coronary artery occlusion were produced with an occluder around the left anterior descending coronary artery in the presence or absence of glibenclamide (10-5 M, topically), which inhibits ATP-sensitive potassium channels, or of vehicle. During topical application of vehicle (0.01% dimethyl sulfoxide), there was dilatation of small (<100 μm diameter) arterioles during reductions in perfusion pressure (percent change in diameter: 6.7±1.5%, 11.7±3.5%, and 10.4±5.1% during mild stenosis, critical stenosis, and complete occlusion, respectively). In the presence of glibenclamide, arteriolar dilatations during coronary stenoses and occlusions were abolished. Glibenclamide did not affect responses of arterioles > 100 μm. Glibenclamide did not alter microvascular responses to nitroprusside. These data suggest that ATP-sensitive potassium channels play an important role in determining the coronary microvascular response to reductions in perfusion pressure.

KW - Autoregulation

KW - Coronary arterioles

KW - Glibenclamide

KW - Intravital microscopy

KW - Ischemia

KW - Microcirculation

UR - http://www.scopus.com/inward/record.url?scp=0026070148&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0026070148&partnerID=8YFLogxK

U2 - 10.1161/01.RES.69.4.1146

DO - 10.1161/01.RES.69.4.1146

M3 - Article

C2 - 1934341

AN - SCOPUS:0026070148

VL - 69

SP - 1146

EP - 1151

JO - Circulation Research

JF - Circulation Research

SN - 0009-7330

IS - 4

ER -