Several Potassium Conductances Modulate the Excitability of Frog Motor Nerve Terminals

  • G. David
  • Y. Yaari
Part of the Topics in the Neurosciences book series (TNSC, volume 1)


A nerve impulse propagating along a motor axon normally initiates a single action potential at points where the unmyelinated terminals branch off from their parent axon. In some vertebrate nerve-muscle preparations, this action potential continues to propagate actively along some portion of the nerve terminals (17), whereas in others it most probably depolarizes the terminals by only a passive spread of current (7). In either case, the resultant depolarization of the nerve terminals Is sufficient to trigger the synchronous release of the transmitter, acetylcholine (ACh), Into the junctional cleft.


Nerve Terminal Outward Current Motor Axon Motor Nerve Terminal Spike Potential 
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© Martinus Nijhoff Publishing, Boston 1986

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  • G. David
  • Y. Yaari

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