Collateral response to activation of potassium channels in vivo

K G Lamping

doi:10.1007/s003950050074

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Collateral response to activation of potassium channels in vivo

Journal article

Peer reviewed

Collateral response to activation of potassium channels in vivo

K G Lamping

Basic research in cardiology, Vol.93(2), pp.136-142

04/1998

DOI: 10.1007/s003950050074

PMID: 9601581

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Abstract

Activation of ATP-sensitive K+ channels is involved in the coronary vascular response to decreases in perfusion pressure and ischemia. Since activation of ATP-sensitive K+ channels in collateral vessels may be important in determining flow to collateral-dependent myocardium, the ability of collaterals to respond to activation of the channel was tested. In the beating heart of dogs, we compared responses of non-collaterals less than 100 microns in diameter to collaterals of similar size using computer-controlled stroboscopic epi-illumination of the left ventricle coupled to a microscope-video system. Aprikalim, a selective activator of ATP-sensitive K+ channels (0.1-10 microM) produced similar dose-dependent dilation of non-collaterals and collaterals. Relaxation was decreased by inhibition of ATP-sensitive K+ channels with glibenclamide, but not by inhibition of nitric oxide synthase with nitro-L-arginine. Bradykinin (10-100 microM) produced similar dilation of non-collaterals and collaterals which was decreased by nitro-L-arginine but not glibenclamide. Thus, in microvascular collaterals, relaxation to both nitric oxide and activation of ATP-sensitive K+ channels is similar to non-collaterals.

Potassium Channels - physiology

Male

Microcirculation - anatomy & histology

Nitroprusside - pharmacology

Microcirculation - drug effects

Dose-Response Relationship, Drug

Heart Rate - drug effects

Glyburide - pharmacology

Female

Pyrans - pharmacology

Bradykinin - pharmacology

Coronary Vessels - anatomy & histology

Collateral Circulation - drug effects

Picolines - administration & dosage

Coronary Vessels - drug effects

Picolines - pharmacology

Vasodilator Agents - pharmacology

Acetylcholine - pharmacology

Enzyme Inhibitors - pharmacology

Nitroarginine - pharmacology

Animals

Dogs

Hemodynamics - drug effects

Bradykinin - administration & dosage

Pyrans - administration & dosage

Details

Title: Subtitle: Collateral response to activation of potassium channels in vivo
Creators: K G Lamping - Medical Services , VA Medical Center, Iowa City 52246, USA. kathryn-lamping@uiowa.edu
Resource Type: Journal article
Publication Details: Basic research in cardiology, Vol.93(2), pp.136-142
DOI: 10.1007/s003950050074
PMID: 9601581
ISSN: 0300-8428
eISSN: 1435-1803
Grant note: HL 39050 / NHLBI NIH HHS
Language: English
Date published: 04/1998
Academic Unit: Cardiovascular Medicine; Neuroscience and Pharmacology; Internal Medicine
Record Identifier: 9984094723602771

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8 Times Cited - Web of Science