Development a new dual wavelength measurement optical recording system of membrane potential from multiple site simultaneously using urtra-high luminance light emitting diode for the light source

我们开发了一种光学系统，用于监测心脏和肌肉等收缩组织的膜电位。在从这种制备中记录的光信号中，由收缩产生的光散射分量与膜电位变化分量重叠。可以利用波长依赖性的差异来分离这两种成分。在多个区域同时进行双波长记录的情况下，切换入射光波长的斩波方法与用二向色镜划分光路的方法相比具有很大的优势。但是，在传统的机械方法中，转换速度不够快，无法用于心脏或肌肉的准备。在光源中引入超高亮度发光二极管，使高速双波长斩波测量记录系统的发展成为可能。前两年，我们复制了东京医科和牙科大学的1020点光学记录系统，这是Hirota（首席研究员）开发的。基本不变，但连续记录时间从一秒增加到几十分钟。其次，我们利用超高亮度发光二极管开发了光源，并对记录系统进行了改造以适应光源斩波。利用这种新系统，我们成功地记录了在大鼠心房呈椭圆形传播的激发波。由于每个元素下的细胞都被大跳动所取代，因此跳动必须被抑制，但使用这种双波长同步记录系统，很容易使用计算机软件自动检测每个像素的兴奋开始时间。

We have developed optical system for monitoring the membrane potential from contracting preparations such as heart and muscle. In optical signal recorded from such preparations, the light-scattering component derived from the contraction is overlapped to the component of membrane potential change. It is possible to separate these two components using the difference in wavelength dependency. In dual wavelength recording from many regions simultaneously, the chopping method for switching the wavelength of the incident light has great advantages compared with that for dividing the optical path by dichroic mirror. But the switching speed, in conventional mechanical method, is not fast enough for heart or muscle preparation. Introducing ultra-high luminance light emitting diode into the light source made it possible to develop the recording system with measurement by high speed dual wavelength chopping. First two years, we made a copy of 1020-site optical recording system in Tokyo Medical and Dental university, which Hirota (Head investigator) developed. It is basically same, but the continuous recording time was expanded from one second to several tens of minutes. Second, we developed a light source using ultra-high luminance light emitting diode, and the remodeling the recording system for fitting the light source chopping. Using this new system, we succeeded in recording an excitation wave spreaded on the rat atrium in oval form. Since the cell under each element had been replaced with the big beating, the beating had to be suppressed, but using this dual wavelength simultaneous recording system, it is easy to automatically detect the time for the excitement beginning in each pixel using computer software.