The effect of tetramethylammonium on single sodium channel currents.
نویسندگان
چکیده
Voltage-dependent Na conductance of rat myotubes was studied by patch recordings of single-channels. The patches were excised from the cell with the patch electrode, and the cytoplasmic surface was bathed in either CsF or tetramethylammonium (TMA)-F. Inward currents were examined from -20 to -50 mV. In this range Cs and TMA both appeared to be nearly impermeant, but TMA blocked the channel in a voltage-dependent manner. A first-order blocking site was located a maximum of 89% of the way through the membrane field from the cytoplasmic surface.
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عنوان ژورنال:
- Biophysical journal
دوره 36 2 شماره
صفحات -
تاریخ انتشار 1981