Disruption of actin cytoskeleton attenuates sulfonylurea inhibition of cardiac ATP-sensitive K+ channels

Two actin filament-depolymerizing agents, DNase I and cytochalasin D, were used to examine the involvement of the cytoskeleton in the functional interaction between the sulfonylurea receptor (SUR) and the ATP-sensitive K+ (KATP) channels. Isolated rate ventricular cardiomyocytes were studied using o...

Full description

Saved in:

Bibliographic Details
Published in:	Pflügers Archiv Vol. 434; no. 2; pp. 203 - 205
Main Authors:	Yokoshiki, H, Katsube, Y, Sunugawa, M, Seki, T, Sperelakis, N
Format:	Journal Article
Language:	English
Published:	Germany Springer Nature B.V 01-06-1997
Subjects:	Actins - metabolism Adenosine Triphosphate - pharmacology Animals Cells Cytochalasin D - pharmacology Cytoskeleton Cytoskeleton - drug effects Deoxyribonucleases - pharmacology Heart - drug effects Potassium Channels - drug effects Proteins Rats Sulfonylurea Compounds - pharmacology
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Two actin filament-depolymerizing agents, DNase I and cytochalasin D, were used to examine the involvement of the cytoskeleton in the functional interaction between the sulfonylurea receptor (SUR) and the ATP-sensitive K+ (KATP) channels. Isolated rate ventricular cardiomyocytes were studied using open cell-attached patches for single-channel recording. Bath application of DNase I (100 microg/ml) or cytochalasin D (10 microM) stimulated the KATP channel activities (in presence of 30 microM ATP), and these channels became resistant to inhibition by tolbutamide (0.5 mM). After exposure to tolbutamide, the relative NPo value was 0.09 +/- 0.02 in control patches in absence of actin disrupters, and 0.67 +/- 0.22* or 0.65 +/- 0.10, respectively, in cells treated with DNase I or cytochalasine D (P < 0.05 vs. control). The inhibitory action of glibenclamide (10 microM) on the KATP channels was also attenuated by DNase I. Thus, the disruption of the actin cytoskeleton attenuates the ability of SUR to inhibit the opening of KATP channels.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0031-6768 1432-2013
DOI:	10.1007/s004240050384