Calcium-independent synaptic transmission: artifact or fact?

Trends Neurosci. 1996 Apr;19(4):120-5. doi: 10.1016/s0166-2236(96)80017-8.


The release of neurotransmitters at classical chemical synapses occurs via Ca2+ influx through voltage-dependent Ca2+ channels, which are opened following depolarization of presynaptic terminals. However, owing to a persistence or increase in the amount of transmitter released in preparations containing low concentrations of Ca2+, it has been proposed that transmitter release could also occur through a Ca(2+)-independent, carrier-mediated process. On the other hand, lowering extracellular [Ca2+] can actually promote Ca2+ influx through voltage-activated Ca2+ channels via a modification of the surface potential of plasma membranes. Therefore, the proposed Ca(2+)-independent transmitter release could be re-accommodated within the framework of the Ca2+ hypothesis of synaptic transmission by taking into account the surface-charge effects.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Artifacts
  • Calcium / physiology*
  • Synaptic Transmission / physiology*


  • Calcium