Single channel potassium currents of the anomalous rectifier
Single channel potassium currents of the anomalous rectifier
复制标题
反常整流器的单通道钾电流
作者：
Y. Fukushima
单通道电流的记录揭示了动作电位的Na和延迟K电流以及乙酰胆碱诱发电流的电导变化的离散事件1 - 5。对异常K整流器的噪声分析表明存在类似的离散事件6,7，其中K电导因超极化或细胞外K离子浓度增加而增加8。我现在使用膜片电流记录技术来研究被囊卵细胞的异常整流。贴片电流中脉冲事件的统计数据与异常整流器的失活动力学一致。外推的类脉冲事件的零电流电位近似等于总异常K电流。在50 mM K溶液中，单通道电导为5.2 pS。
The recording of single channel currents has revealed the discrete events underlying the conductance changes for the Na and delayed K currents of the action potential, as well as those underlying acetylcholine-evoked currents1–5. The existence of similar discrete events has been suggested by noise analysis of the current termed anomalous K rectifier6,7, in which a K conductance is increased by hyperpolarization or by an increased extracellular concentration of K ions8. I have now used the patch current recording technique to investigate the anomalous rectifier of the tunicate egg cell. The statistics of pulse-like events in the patch current were found to be consistent with the inactivation kinetics of the anomalous rectifier. The extrapolated zero-current potential of the pulse-like events was approximately equal to that of the total anomalous K current. The single channel conductance was 5.2 pS in 50 mM K solution.