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

我们已经开发了光学系统，用于监测心脏和肌肉等收缩制剂的膜电位。在从这种制剂记录的光学信号中，由收缩产生的光散射分量与膜电位变化的分量重叠。可以使用波长依赖性的差异来分离这两个分量。在同时从多个区域进行双波长记录时，与用二向色镜分割光路的方法相比，切换入射光波长的斩波法具有很大的优势。但在传统的机械方法中，切换速度不够快，不能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研制成为可能。头两年，我们在东京医科大学复制了由Hirota(首席研究员)开发的1020个位置的光学记录系统。基本相同，但连续记录时间从一秒延长到几十分钟。其次，我们研制了一种采用超高亮度发光二极管的光源，并对记录系统进行了改造，以适应光源的斩波。利用这个新系统，我们成功地记录到一个椭圆形的激发波传播在大鼠心房上。由于每个元素下的细胞都被大跳动取代，因此必须抑制跳动，但使用这种双波长同时记录系统，很容易利用计算机软件自动检测每个像素开始兴奋的时间。

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.