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为了研究耳蜗外毛细胞的基本电生理特性，应用细胞膜片钳制技术对豚鼠耳蜗外毛细胞底侧膜的高电导的钾通道进行了初步研究。结果显示，其高电导钾通道有以下典型特征：①具有明显的电压依赖性。在膜去极化时，通道被激活，其去极化程度越高，通道活动越强。在非对称性钾浓度梯度下，其反转电位为－３０ｍＶ，斜率电导约１３３±３ｐＳ（ｎ＝５）；②通道活动能被特异性阻断剂四乙胺（ＴＥＡ）在较高浓度下（＞１０ｍｍｏｌ／Ｌ）阻断，ＴＥＡ的阻断效应呈浓度依赖性；③胞浆内钙浓度的增高，能显著激活该通道，增加其开放概率和平均开放时间。上述结果表明：豚鼠耳蜗外毛细胞存在着高电导的电压依赖的钙激活的钾通道。该研究为进一步开展通道活动的调控，以及药物等因素对通道活动影响的研究，提供了有价值的资料。
In order to study the basic electrophysiological properties of cochlear outer hair cells, the cell membrane clamp technique was used to study the high conductance potassium channel in the basolateral membrane of guinea pig cochlear outer hair cells. The results showed that the high-conductivity potassium channel has the following typical features: ① has a significant voltage-dependent. When membrane depolarization, the channel is activated, the higher the degree of depolarization, the more channel activity. The reversal potential was -30mV and the conductivity was about 133 ± 3pS (n = 5) under the gradient of asymmetry potassium concentration. ② The channel activity could be inhibited by the specific blocker tetraethylamine (TEA) at higher concentration (> 10mmol / L) blockade, TEA blockade effect was concentration-dependent; ③ increased intracellular calcium concentration, can significantly activate the channel to increase the open probability and the average open time. The above results show that there is a highly conductive voltage-dependent calcium-activated potassium channel in guinea pig cochlear outer hair cells. The study provides valuable information for further research on the regulation of channel activities and the influence of drugs and other factors on the channel activities.