髓袢升支粗段管周膜钾通道电流特性的研究

Properties of currents through potassium channels in basolateral membrane of the thick ascending limb

目的研究肾脏髓袢升支粗段管周膜钾通道的类型及其电流特征。方法应用单通道膜片钳技术记录大鼠肾脏髓袢升支粗段管周膜钾通道电流。结果在髓袢升支粗段上皮细胞的管周膜可记录到多种单通道钾电流。其中,50pS、70pS和100pS 3种钾通道占90%以上,不同类型钾通道的电流大小、开放概率及开放时间和关闭时间不同。结论髓袢升支粗段管周膜存在不同类型的钾通道,这些通道具有不同的电流特性。

Objective To investigate the currents through different types of K＋ channels in basolateral membrane of the thick ascending limb of rats.Methods Single channel patch-clamp technique was applied to record the currents through different K＋ channels in basolateral membrane of the thick ascending limb of rats.Results Various single K＋ channel currents were recorded in basolateral membrane of the thick ascending limb of rats.Over 90% currents were mediated with 50pS,70pS and 100pS K＋ channels.The current amplitude,open frequency,mean open time and mean close time of each K＋ channel were characteristic.Conclusion Various types of K＋ channels,which mediate different characteristic currents,exist in basolateral membrane of the thick ascending limb.