Sodium channels in planar lipid bilayers. Channel gating kinetics of purified sodium channels modified by batrachotoxin.
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Sodium channels in planar lipid bilayers. Channel gating kinetics of purified sodium channels modified by batrachotoxin
Single channel currents of sodium channels purified from rat brain and reconstituted into planar lipid bilayers were recorded. The kinetics of channel gating were investigated in the presence of batrachotoxin to eliminate inactivation and an analysis was conducted on membranes with a single active channel at any given time. Channel opening is favored by depolarization and is strongly voltage de...
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The guanidinium toxin-induced inhibition of the current through voltage-dependent sodium channels was examined for batrachotoxin-modified channels incorporated into planar lipid bilayers that carry no net charge. To ascertain whether a net negative charge exists in the vicinity of the toxin-binding site, we studied the channel closures induced by tetrodotoxin (TTX) and saxitoxin (STX) over a wi...
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We have observed the opening and closing of single batrachotoxin (BTX)-modified sodium channels in neuroblastoma cells using the patch-clamp method. The conductance of a single BTX-modified channel is approximately 10 pS. At a given membrane potential, the channels are open longer than are normal sodium channels. As is the case for normal sodium channels, the open dwell times become longer as t...
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ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 1986
ISSN: 0022-1295,1540-7748
DOI: 10.1085/jgp.88.1.1