alexa ATP-sensitive potassium channels in adult mouse skeletal muscle: different modes of blockage by internal cations, ATP and tolbutamide.
Diabetes & Endocrinology

Diabetes & Endocrinology

Journal of Thyroid Disorders & Therapy

Author(s): Woll KH, Lnnendonker U, Neumcke B

Abstract Share this page

Abstract Single ATP-sensitive K channels were studied in membrane patches excised from enzymatically dissociated mouse toe muscle. The channel conductance is 74 pS in symmetrical 160 mM KCl solutions. Replacement of K+ by Na+ in the internal solution or 2 mM internal Ca2+ or Mg2+ induced a rectification of the current-voltage curve at positive potentials. No change of the current-voltage curve was observed by adding small amounts of the channel blockers ATP (20-100 microM) or tolbutamide (0.5 mM) to internal 160 mM KCl solutions. The openings of the channel occurred in bursts. Open (tau o), closed (tau c) times within bursts and pauses (tau p) between bursts were determined over a wide range of positive and negative membrane potentials. At increasing potentials tau o increases, tau c reaches a minimum near 0 mV and tau p decreases. According to the voltage dependence and the time scale of channel blockage three types of blocking agents could be distinguished: (i) small internal cations (Na+, Ca2+, Mg2+) are "fast" blockers at positive voltages; at negative voltages they decrease tau o and increase tau c. (ii) Internal ATP anions produce a voltage-dependent decline of the open-state probability and strongly decrease tau o. (iii) Tolbutamide causes a voltage-independent decrease of the open-probability and its main effect is an increase of tau p. The results suggest that the ATP-sensitive K channel has an internal gate like those of other voltage-gated cation channels and that different blockers interfere with different transitions in channel gating.
This article was published in Pflugers Arch and referenced in Journal of Thyroid Disorders & Therapy

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

1-702-714-7001Extn: 9037

Business & Management Journals


1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

1-702-714-7001 Extn: 9042

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version