Development of Ultra-high Power Video Microscope for Patch Clamp Study.

这个研究项目的目的是开发一个系统，通过这个系统我们可以同时测量贴片形状、单通道电流、贴片电容和移液器压力。该系统由超高功率差干涉视频显微镜、高速油压发生器、无漂移机械机械手、膜片箝位放大器、锁相放大器、带帧采集器和A/D、D/A转换器的386个人计算机组成。各部件的规格如下：1。视频显微镜：一种改良的倒置光学显微镜（Olympus IMT-II），带有视频，总放大倍数为15nm/像素。压力发生器：油驱动压力发生器，带伺服控制器，上升时间2毫秒，动态范围<±> 200mmH3。微机械臂：由电动滑块和脉宽、高度调制伺服控制器组成无漂移（0.2 μ m/5 min）微机械臂。电流和电容测量：1将正弦波送入膜片钳放大器的命令输入端，将输出分离为单通道电流（0.1 pA）和电容电流（0.1 fF），后者送入锁相放大器。图像处理：使用带有帧采集器（DT2851）的386个人计算机获取补丁图像。构造了一个简单的TIME CODE解码来抓取任意帧的图像。数据采集：A/D。采用D/A转换器获取多路电信号。时间码被用来使图像与电子信号同步。利用该系统可以可视化膜片膜，得到拉伸激活通道的张力与活度关系。

The aim of this research project is to develop a system by which we can make simultaneous measurements of patch shape, single channel currents, patch capacitance, and pipette pressure. The system is composed of ultra-high power differential interference video microscope, high speed oil driven pressure generator, drift free mechanical manipulator, patch clamp amplifier, phaselock amplifier, and 386 based personal computer with frame grabber and A/D, D/A converter. The specification of each component is as follows.1. Video microscope : A modified inverted light microscope (Olympus IMT-II) with video gave a total magnification of 15nm/pixel.2. Pressure generator : Oil driven pressure generator with servo controller gave a rise time of 2 msec and a dynamic range of <plus-minus> 200mmH3. Micromanipulator : Drift-free (0.2 mum/5 min) micro manipulator was constructed from motorized sliders combined with pulse-width and height modulated servo controller.4. Current and capacitance measurement : 1 Sinusoidal wave was fed into the command input of the patch clamp amplifier and the resulting output was separated into single channel currents (0.1 pA) and capacitive currents (0.1 fF), the latter of which was fed into the phaselock amplifier.5. Image processing : 386 based personal computer with a frame grabber (DT2851) was used to acquire patch images. A SIMPLE TIME CODE decorder was constructed to grab images of arbiterary frames.6. Data acquisition : A/D. D/A converter was used to aquire multi-channel electrical signals. The time code was used to synchronize images with electrical signals.By using this system we could visualize patch membranes and get tension vs. activity relationship of stretch activated channels.