Ma Baofeng, Xu Guangjin, Wang Wei, Enyeart John J, Zhou Min
Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
Mol Brain. 2014 Mar 17;7:18. doi: 10.1186/1756-6606-7-18.
Whole-cell patch clamp recording has been successfully used in identifying the voltage-dependent gating and conductance properties of ion channels in a variety of cells. However, this powerful technique is of limited value in studying low membrane resistance cells, such as astrocytes in situ, because of the inability to control or accurately measure the real amplitude of command voltages. To facilitate the study of ionic conductances of astrocytes, we have developed a dual patch recording method which permits membrane current and membrane potential to be simultaneously recorded from astrocytes in spite of their extraordinarily low membrane resistance. The utility of this technique is demonstrated by measuring the voltage-dependent activation of the inwardly rectifying K+ current abundantly expressed in astrocytes and multiple ionic events associated with astrocytic GABAA receptor activation. This protocol can be performed routinely in the study of astrocytes. This method will be valuable for identifying and characterizing the individual ion channels that orchestrate the electrical activity of low membrane resistance cells.
全细胞膜片钳记录已成功用于识别多种细胞中离子通道的电压依赖性门控和电导特性。然而，由于无法控制或准确测量指令电压的实际幅度，这种强大的技术在研究低膜电阻细胞（如原位星形胶质细胞）时价值有限。为了便于研究星形胶质细胞的离子电导，我们开发了一种双膜片记录方法，该方法能够同时记录星形胶质细胞的膜电流和膜电位，尽管它们的膜电阻极低。通过测量星形胶质细胞中大量表达的内向整流钾电流的电压依赖性激活以及与星形胶质细胞GABAA受体激活相关的多个离子事件，证明了该技术的实用性。该方案可在星形胶质细胞研究中常规进行。这种方法对于识别和表征协调低膜电阻细胞电活动的单个离子通道将具有重要价值。
