一种改进型膜片钳放大器真电流钳的研究

True Current Clamp-analysis and Improvement of Current Clamp in the Conventional Patch Clamp Amplifier

膜片钳技术在细胞膜兴奋性的研究中起着关键性的作用。传统的膜片钳放大器主要目的是用于电压钳实验,而在电流钳实验中它有着固有的缺陷,包括电流钳位的误差和动作电位测量信号的失真和畸变,以及容易引起振荡而击死细胞。本文采用系统传递函数的方法对传统的膜片钳放大器电流钳的固有缺陷进行分析,提出了“真电流钳”改进方案,在膜片钳放大器上进行了改造和测试。测试结果表明真电流钳克服了传统膜片钳放大器电流钳的缺陷,并且保持了原有的主要性能。

Patch clamp techmque plays an important role m the studtes of excciable cell membrane. Conventional patch clamp amplifier was originally designed for the main purpose of voltage clamp experiments. However, in current clamp experiments intrinsic defects were exhibited including error in current clamping, distortion of recorded action potential signal and oscillations tending to kill cells. In this paper these defects were analyzed by the method of system transfer function and the improved solution “true current clamp” was proposed. Results showed that this solution succeeded in the improvement of current clamp in conventional patch clamp amplifier without degrading the original performance.