Study for the dynamics of the intracellular Ca concentration changes with high spatial and temporal resolution.

我们利用电流镜装置，结合CCD电视摄像机和图像处理机，制作了一种将两个激发波长以视频速率转换为荧光染料的仪器。通过该装置，我们可以记录Fura-2在两个激发波长的荧光变化，间隔33毫秒，以监测细胞内钙离子浓度的变化。这些成对的荧光图像数据给出了细胞内钙离子浓度以66毫秒的速度变化的轮廓。该装置由两部分组成。第一部分是电流镜装置本身，用于切换两个激发波长。第二部分是用来实现检流镜装置与摄像系统同步的控制逻辑电路和帧处理系统。由于视频图像的单帧是由两个隔行扫描的场组成的，所以在两个分量场叠加期间，CCD摄像机的快门打开时间仅为15毫秒。…上光强的降低采用像增强器耦合的CCD摄像机对多个摄像头进行补偿。同步所有三个组件设备(电流镜设备、CCD相机和帧处理器)很简单，但尝试图像集成以提高荧光图像的信噪比相对困难。我们已经克服了这个问题，我们采用了集成电路来划分时钟频率，并通过同步帧积分的开始和电流镜装置的开始来克服这个问题。我们还没有在生理实验中广泛应用这种装置。然而，我们已经成功地记录了鸡脑干培养神经元细胞内钙离子浓度的变化，无论是在普通电视速率成像模式下还是在帧积分的较慢速率模式下。该斩波装置基本无振动，有望应用于电生理学实验中，同步记录细胞内离子浓度的变化和细胞的电活动。较少

We have made an instrument for exchanging two excitation wavelengths for fluorescence dye at the vide-rate by utilizing a galvano-mirror device, combining with a CCD TV camera and a frame processor. By this device, we could record fura-2 fluorescence changes at two excitation wavelengths at 33 msec time intervals to monitor intracellular Ca ionic concentration changes. These paired fluorescence image data give the profile of intracellular Ca ionic concentration changes at the rate of 66 msec. The device is made from two part. The first part is the galvano-mirror device itself and switches the two excitation wavelengths. The second part is a control logic circuit for synchronizing the galvano-mirror device with the image recording CCD camera, and the frame processing system. Since a single frame of a video-image is made of two interlacing fields, the CCD camera is shutter opened for only 15msec during the two component fields are superimposed. The reduction of the light intensity on the … More camera-head is compensated by using an image intensifier coupled CCD camera. It was simple to synchronize all three component devices (the galvano-mirror device, the CCD camera, and the frame processor), but the attempt for image integration for improving the signal to noise ratio of the fluorescence images was relatively hard to be achieved. We have overcome the problem by adopting an integrated circuit for dividing a clock rate and by synchronizing the start of the frame integration with the start of galvano-mirror device.We have not yet applied this device extensively for the physiology experiments. However, we have already succeeded in recording intracellular Ca ionic concentration changes from cultured neurons from the brain stem of a chick, in both at the ordinary TV rate imaging mode and at a slower rate mode with the frame integration. This chopper device is basically vibration-free, and it is expected to be applied in the electrophysiology experiments to record intracellular ionic concentration changes simultaneously with the electrical activity of the cell. Less