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钾离子通道功能与细胞的兴奋性有关，在豚鼠支气管平滑肌细胞膜上，用膜片钳技术证实了一类电压依赖性钾通道的存在，该通道电导为７５±５ｐＳ，翻转电位为－７３±８ｍＶ．动力学特性显示，通道开放时程分布直方图符合双指数拟合．其中τ０２随去极化程度增大而增大．通道开放概率有明显的电压依赖性．该类通道可被四乙胺从膜的内，外侧面阻断，对４－氨基吡啶不敏感．可被铯离子阻断，通道活动与细胞内钙水平降低无关．提示钾离子通道特性在不同组织细胞上有差异．
The function of potassium channel is related to the excitability of cells. In the guinea pig bronchial smooth muscle cell membrane, patch-clamp technique was used to confirm the existence of a voltage-dependent potassium channel with a conductance of 75 ± 5 pS and a reversal potential of -73 ± 8 mV . Kinetic properties show that the histogram of open-channel temporal distribution matches the double-exponential fit. Which τ02 increases with the degree of depolarization increased. Channel open probability has obvious voltage dependence. This kind of channel can be tetraethylamine from the membrane inside and outside the block, is not sensitive to 4-aminopyridine. Can be cesium ion blockade, channel activity and intracellular calcium level has nothing to do. Tip potassium channel characteristics in different cells have differences.