Electro-pharmacological profiles of two brain mitoplast anion channels
Loading...
Date
2017-04-18
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
We have characterized the conduction and blocking properties of two different chloride channels
from brain mi- tochondrial inner membranes after incorporation into planar lipid bilayers. Our
experiments revealed the existence of channels with a mean conductance of 158 ± 7 and 301 ± 8 pS in
asymmetrical 200 mM cis/50 mM trans KCl solutions. We determined that the channels were ten times
more permeable for Cl− than for K+, calculated from the reversal potential using the Goldman-Hodgkin-Katz equation. The channels were bell-shaped voltage depend- ent, with maximum open probability 0.9 at ± 20 mV. Two mitochondrial chloride channels were blocked after the addition of 10 µM DIDS. In addition, 158 pS chloride channel was blocked by 300 nM NPPB, acidic pH and 2.5 mM ATP, whereas the 301 pS chloride channel was blocked by 600 µM NPPB but not by acidic pH or ATP. Gating and conducting behaviors of these channels were unaffected by Ca2+. These results demonstrate that the inner membrane, is probably identical to IMAC and 301 pS Cl channel displays different properties than those classically described for mitochondrial anion channels.
Description
Table of contents
Keywords
mitochondria, chloride channels, single channel, intracellular ion channels, brain, mitoplast