Further Studies on Depolarization Release Coupling in Squid Giant Synapse

  • R. Llinás
  • M. Sugimori
  • K. Walton
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 221)


During the past few years significant information has been accumulated concerning the physiological and biochemical properties by which presynaptic membrane depolarization leads to transmitter release in chemical synapses. The physiological aspects of this property of pre-terminals is often referred to as “depolarization-release coupling” and is known to be a function of intracellular calcium concentration at the appropriate cytosolic compartment (cf. Llinas, 1982). Most of the information relating to this aspect of synaptic transmission has come from recent studies in the squid stellate ganglia (Llinas, Steinberg and Walton, 1976–1981; Llinas, Sugimori and Simon, 1982; Charlton, Smith and Zucker, 1982; Augustine and Eckert, 1984; Augustine, Charlton and Smith, 1985a,b; Simon and Llinas, 1985; Llinas, McGuiniess, Leonard, Sugimori and Greengard, 1985) and frog and crayfish neuromuscular junctions (Mallart and Martin, 1967; Dudel 1983 a,b; Parnas et al., 1984). Among these the squid giant synapse continues to be a most useful preparation, particularly when studying those aspects of the release function which require injections of materials into the presynaptic terminal or the direct measurement of the presynaptic Ca. In this paper we would like to address three main issues, (i) the effects of direct injection of Ca ions into the presynaptic terminal on transmitter release, (ii) voltage dependence of Ca-dependent release, and (iii) the temperature dependence of transmitter release.


Transmitter Release Voltage Clamp Presynaptic Terminal Synaptic Delay Postsynaptic Response 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • R. Llinás
    • 1
  • M. Sugimori
    • 1
  • K. Walton
    • 1
  1. 1.Department of Physiology and BiophysicsNew York University Medical CenterNew YorkUSA

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