雑誌文献を検索します。書籍を検索する際には「書籍検索」を選択してください。

検索

書誌情報 詳細検索 by 医中誌

Japanese

Morphological Basis of Synaptic Transmission Koji Uchizono 1 1Department of Physiology, Faculty of Medicine, University of Tokyo pp.761-773
Published Date 1965/12/25
DOI https://doi.org/10.11477/mf.1431904245
  • Abstract
  • Look Inside

Chemical nature of synaptic transmission hasbeen established both electrophysiologically andpharmacologically. Bennett and De Robertis showedelectron microscopically a specific structure at thesynaptic sites of neuromuscular junctions. Thepresent author assumed that the number of thesynaptic vesicles would be changed if the strongelectrical stimuli were given to the preganglionicnerve trunk. In order to scrutinize this hypothesiselectrical stimuli were applied to the preganglionicnerve trunk of amphibian sympathetic ganglion. 25 per second stimuli of rectangular pulses wereused as the most effective stimulation of thesynapses. Microelecrodes were inserted into aneuron to control the time of fixation of theganglion. Membrane resting and action potentialsof a neuron were displayed on the screen of theoscilloscope. About ten minutes after the stimuluswas begun, marked changes in the membraneaction potentials, although slight changes of theresting membrane potentials were also recognized on the oscilloscope screen. The flexion on the rising phase of the action potentials was recognized quite often. Later on action potentials were separated from the EPSYs, the latter being maintained until later. But at the end of the stimulation almost no trace of EPSPs was displayed on the screen of the oscilloscope. At this moment OsO4 solution was poured on to the ganglion to fix it momemtarily. Electrical events disappeared instantaneously. After dehydration and embedding the ganglion was investigated by the electron microscope. Drastic changes were proved in the synapses of neurons. In some of the synapses the number of the synaptic vesicles was reduced to the minimum, leaving the recidual substance only in the empty space of the synapses. Drastic changes were also recognized in the cytoplasm of a neuron. Droplets in the cytoplasm of a neuron decreased in number and many vacuoles were left at the sites of the droplets, suggesting that the preganglionic nerve stimuli gave rise to a drastic change in the cytoplasm of a postganglionic neuron. It may be concluded that the synaptic vesicles of theamphibian sympathetic ganglion are essentially related to the synaptic transmission in neurons ofthe sympathetic ganglion of amphibia.


Copyright © 1965, Igaku-Shoin Ltd. All rights reserved.

基本情報

電子版ISSN 1882-1243 印刷版ISSN 0001-8724 医学書院

関連文献

もっと見る

文献を共有