MECHANICAL, THERMAL, AND OPTICAL SIGNS OF EXCITATION IN THE NERVOUS SYSTEM

我们在本财政年度集中展示 与突触相关的神经组织的快速结构变化 活动 电鳐的电器官，鱼雷是众所周知的， 非常适合于研究突触传递机制 因为它的同质性和大量的胆碱能神经支配。 使用在此制造的灵敏的机械和光学器件， 我们在实验室里发现，电刺激其中一条神经 进入器官后会迅速肿胀， 器官萎缩。 此外，通过使用特殊的热传感器， 我们设计了一个人造的，我们能够证明， 快速产热，随后器官缓慢吸热。 请注意，以前的研究人员使用的听觉传感器具有 响应时间约为100毫秒，我们有必要构建一个 新型热传感器，具有高的时间分辨率， 完全与电器官屏蔽以直接刺激。 使用 一个小的铝杆连接到一个小的器官片条， 已经确定，器官中的电细胞对 化学递质（从神经末梢释放的乙酰胆碱）， 迅速膨胀然后缓慢收缩。 此外，我们还发现， 脑片中突触后电位的产生 通过快速产热随后缓慢吸热。 我们 我相信这些发现有力地支持了化学物质的理论。 Neumann，Nachmansohn和Katchalsky（1973- 1976）;该理论提出受体蛋白分子具有 对钙离子和化学递质的结合能力大， 结合的Ca-离子和化学递质的释放导致释放 受体分子中结合的钙离子。 更详细的 目前正在审查这一理论的有效性。

we have concentrated during this fiscal year on the demonstration of rapid structural changes in nervous tissues associated with synaptic activities. the electric organ of the electric ray, Torpedo is known to be well suited for t he study of the mechanism of synaptic transmission because of its homogeneity and its massive cholinergic innervation. Using sensitive mechanical and optical devices fabricated in this laboratory we have found that electric stimulation of one of the nerves entering into the organ produces rapid swelling followed by slow shrinkage of the organ. Furthermore by use of special heat-sensors which we have designed an fabricated we were able demonstrate that there is rapid heat production followed by slow heat absorption by the organ. Note that the hear-sensor employed by previous investigators had a response-time of about 100 msec it was necessary for us to construct a new type of heat-sensor which have a high time-resolution and are completely shielded from the electric organ to direct stimulation. Using a small aluminum lever connected to a small strip of the organ slice we have established that the electrocytes in the organ respond to the chemical transmitter(acetylcholine released from the nerve endings) with rapid swelling followed by slow shrinkage. In addition we have found that generation of a postsynaptic potential in the slice is accompanied by a rapid heat production followed by a slow heat absorption. We believe that these findings give strong support to the theory of chemical excitation put forward by Neumann,, Nachmansohn and Katchalsky (1973- 1976); this theory proposes that the receptor protein molecules have a large binding capacity for Ca-ions and the chemical transmitter causes release of the bound Ca-ions and the chemical transmitter causes release of the bound Ca-ions from the receptors molecules. A more detailed examination of the validity of this theory is in progress.