Axon公司膜片钳系统的漏减分析

目的和方法：采用大鼠海马脑片盲法膜片钳的全细胞记录技术,研究美国Axon公司生产的膜片钳系统（Axopatch放大器和pClamp软件）中几种漏减功能的意义和作用机制,重点对定标P／N漏减（Scaled P/N leak subtraction)、膜片钳放大器漏减以及Clampfit处理软件漏减功能的选择与使用进行分析与比较。结果：Clampex采样软件中的定标P／N漏减功能比P／N漏减功能的噪声要小;放大器漏减功能可漏减单一去极化电压幅度所诱发的漏电流,但不能同时对不同电压幅度系列去极化所产生的稳态漏电流进行追踪漏减;Clampfit漏减功能由于其设定只要膜两侧存在电位差就有漏电流产生,因而不适合在记录电压门控性离子通道电流时对稳态漏电流进行漏减。结论：在研究电压门控性离子通道的性质时,可采用P／N漏减功能或定标P／N漏减功能对稳态漏电流进行漏减,而Clampfit漏减功能是不合适的。

Leak subtraction analysis of Axon patch clamp system

Aim and Methods: Using blind whole cell recording techniques on rat hippocampal slices, the function and mechanisms of several leak subtraction methods of Axon patch clamp system (Axopatch amplifier and pClamp software) were analyzed. That how to select and use scaled P/N leak subtraction, patch clamp amplifier leak subtraction and Clampfit leak subtraction were emphasized in our present study. Results: The noise induced by scaled P/N leak subtraction of Clampex soft ware was smaller than that of P/N leak subtraction. Axon patch clamp amplifier leak subtraction could subtract the leak current produced by single depolarizing pulse but not the leak current produced by a series of different step depolarizing pulses. Due to its assumption that leak current would be produced if only potential difference arises across membrane, Clampfit leak subtraction was not suitable to subtracting the steady state leak current while recording voltage gated channel currents. Conclusion: P/N and scaled P/N leak subtraction, but not Clampfit leak subtraction, cad be used to subtract steady state leak current while recording voltage gated channel currents.