Mason M J, Simpson A K, Mahaut-Smith M P, Robinson H P C
Department of Physiology, University of Cambridge, United Kingdom.
Biophys J. 2005 Jan;88(1):739-50. doi: 10.1529/biophysj.104.049866. Epub 2004 Oct 29.
In these experiments we have investigated the feasibility and accuracy of recording steady-state and dynamic changes in transmembrane potential noninvasively across an intact cell-attached patch using the current-clamp mode of a conventional patch-clamp amplifier. Using an equivalent circuit mimicking simultaneous whole-cell voltage-clamp and cell-attached current-clamp recordings we have defined both mathematically and experimentally the relationship between the membrane patch resistance, the seal resistance, and the fraction of the whole-cell potential recorded across an intact membrane patch. This analysis revealed a steep increase in the accuracy of recording of steady-state membrane potential as the seal/membrane ratio increases from 0. The recording accuracy approaches 100% as the seal/membrane ratio approaches infinity. Membrane potential measurements across intact cell-attached patches in rat basophilic leukemia cells and rat megakaryocytes revealed a surprisingly high degree of accuracy and demonstrated the ability of this noninvasive technique to follow dynamic changes in potential in nonexcitable cells.
在这些实验中，我们研究了使用传统膜片钳放大器的电流钳模式，通过完整的细胞贴附膜片无创记录跨膜电位的稳态和动态变化的可行性与准确性。利用一个模拟同时进行全细胞膜电压钳和细胞贴附电流钳记录的等效电路，我们在数学和实验上都定义了膜片电阻、封接电阻以及跨完整膜片记录的全细胞电位分数之间的关系。该分析表明，随着封接/膜片比率从0开始增加，稳态膜电位记录的准确性急剧提高。当封接/膜片比率接近无穷大时，记录准确性接近100%。对大鼠嗜碱性白血病细胞和大鼠巨核细胞完整细胞贴附膜片的膜电位测量显示出惊人的高准确性，并证明了这种无创技术跟踪非可兴奋细胞电位动态变化的能力。
