Sensitivity of high-conductance potassium channels in synaptosomal membranes from the rat brain to intracellular pH

High-conductance potassium channels have been studied in inside-out patches excised from proteoliposomes reconstituted from giant liposomes and rat brain synaptosomes. Acid pH in the medium reduced single channel current amplitude and increased the mean open probability and the frequency of channel...

Full description

Saved in:
Bibliographic Details
Published in:European biophysics journal 1994-04, Vol.23 (1), p.71-77
Main Authors: Habartová, A, Krůsek, J, Zemková, H
Format: Article
Language:English
Subjects:
Animals
Cerebral Cortex - metabolism
Cerebral Cortex - physiology
Cerebral Cortex - ultrastructure
Electrophysiology
Hydrogen-Ion Concentration
In Vitro Techniques
Kinetics
Liposomes
Male
Membrane Potentials - physiology
Potassium Channels - physiology
Rats
Synaptic Membranes - physiology
Synaptosomes - physiology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:High-conductance potassium channels have been studied in inside-out patches excised from proteoliposomes reconstituted from giant liposomes and rat brain synaptosomes. Acid pH in the medium reduced single channel current amplitude and increased the mean open probability and the frequency of channel opening. This was accompanied by a shortening of the open time constant at positive potential and by shortening of the longer closed time constant. The decrease of channel amplitude, the increase of the open probability and the decrease in the longer closed time constant can be explained by neutralization of negative charges of the membrane and by a decrease in the surface membrane potential which mimics membrane depolarization. The shortening of the mean open time is apparently due to a channel blockade by protons.
ISSN:0175-7571
1432-1017
DOI:10.1007/BF00192207