Development of a method of "Voltage Clamp by light" for the study of visual neurons

30多年来，电压钳方法为生理学提供了一种基本的实验范式。然而，在某些情况下，由于细胞形态（大小和形状），与其他细胞的电连接等问题，这是不可行的。这对许多视觉神经元来说是真实的，并且人们通常对重要的主题（如突触机制）了解甚少，以介导光反应。本研究的目的是通过开发一种新的电压钳方法来解决这个问题，该方法利用了视觉系统的自然刺激。即光。我们认为，这一目标已经充分实现，概述如下。“光电压钳“方法的研制（1.1）样机系统：设计制作了一种基于膜电压误差信号自动控制光强的伺服机械装置。(1.2)扩展系统：将电桥平衡法与前面的原型结合，以允许通过光同时测量电压钳下的膜电阻。应用研究一：用（1.1）的装置测量鲤鱼视网膜水平细胞的直流和交流光谱敏感性。从这一结果中得出了一个新的观察结果，与3.3的结果密切相关。应用研究ii：（1.2）的系统用于研究从视锥光感受器到水平细胞的突触机制。这一结果需要对该领域的一个流行概念进行修正.应用研究iii：应用（1.2）的装置发现了与螯虾感光细胞中的光适应过程相关的新现象。

The method of voltage clamp has provided physiology with a basic experimental paradigm for mofe than three decades. It is not, however,feasible in some cases, due to problems arising from the cell morphology (size and shape) , electrical connection with other cells, and etc. This is true with many visual neurons, and often one can learn little about important subjects such as synaptic mechanisms to mediate the photo-response. The purpuse of this research was to get around the problem by developing a new voltage clamp method which makes use of the natural stimulus to the visual system. namely light. We feel that the aim has adequately been attained, as is summarized below.1. Development of the Method of " Voltage Clamp by Light "(1.1) Protype System: a servomechanical apparatus was designed and fabrica ted, which automatically controls the light intensity on the basis of membrane voltage error signal.(1.2) Extended System: the bridge-balance method was incorporeted with the preceding prototype, to allow simultaneous measurement of the membrane resistance under the voltage clamp by light.2. Application Research i: the eqipment of (1.1) was used to measure DC and AC spectral sensitivities of horizontal cells in the carp retina. A new observation was made from this result, bearing close relevance to the finding of 3.3. Application Research ii: the system of (1.2) was used to investigate the synaptic mechanisms from cone photoreceptors to horizontal cells. The result necessitates a revision on a popular notion in this field.4. Application Research iii: the apparatus of (1.2) was applied to find a new phenomenon asscociated with the process of light adaptation in the crayfish photoreceptor cell.