THE ACTION OF EXTERNAL TETRAETHYLAMMONIUM IONS ON UNITARY DELAYED RECTIFIER POTASSIUM CHANNELS OF FROG SKELETAL-MUSCLE
THE ACTION OF EXTERNAL TETRAETHYLAMMONIUM IONS ON UNITARY DELAYED RECTIFIER POTASSIUM CHANNELS OF FROG SKELETAL-MUSCLE
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DOI：
10.1113/jphysiol.1987.sp016833
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发表时间：
1987-12-01
影响因子：
5.5
通讯作者：
STANFIELD, PR
中科院分区：
文献类型：
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作者：
SPRUCE, AE;STANDEN, NB;STANFIELD, PR
1. 我们用单通道记录的方法研究了蛙骨骼肌延迟整流钾通道被细胞外四乙基铵离子（TEA+）阻滞的情况。2. TEA+通过降低单一电流的视振幅来阻断，而没有检测到开电平电流方差的增加。3. TEA+阻断率为1:1，分数电流在5.8 mM和-3 mV处减半。该块的解离常数与电压相关，在138 mV退极化时增加e倍。4. 延迟整流器钾电流的激活不受TEA+的影响。5. 在TEA+的存在下，打开时间表示打开和阻塞事件的爆发，而TEA+不会增加打开时间，这表明阻塞通道能够正常关闭。
1. We have used single-channel recording to investigate the block by extracellular tetraethylammonium ions (TEA+) of delayed rectifier potassium channels of frog skeletal sarcolemma. 2. TEA+ blocks by reducing the apparent amplitude of unitary currents, without detectable increase in open-level current variance. 3. The block by TEA+ appeared to be 1:1, the fractional current being halved at 5.8 mM and -3 mV. The dissociation constant for the block was voltage dependent, increasing e-fold for a 138 mV depolarization. 4. Activation of delayed rectifier potassium currents is not altered by TEA+. 5. Open times, which in the presence of TEA+ represent bursts of open and blocked events, are not increased by TEA+, indicating that blocked channels are able to close normally.