Dissociation between Ca2+-triggered synaptic vesicle exocytosis and clathrin-mediated endocytosis at a central synapse

Neuron. 1998 Sep;21(3):607-16. doi: 10.1016/s0896-6273(00)80570-x.


We have tested whether action potential-evoked Ca2+ influx is required to initiate clathrin-mediated synaptic vesicle endocytosis in the lamprey reticulospinal synapse. Exo- and endocytosis were temporally separated by a procedure involving tonic action potential stimulation and subsequent removal of extracellular Ca2+ (Ca2+e). A low concentration of Ca2+ ([Ca2+]e of 11 microM) was found to be required for the induction of early stages of endocytosis. However, the entire endocytic process, from the formation of clathrin-coated membrane invaginations to the generation of synaptic vesicles, proceeded in the absence of action potential-mediated Ca2+ entry. Our results indicate that the membrane of synaptic vesicles newly incorporated in the plasma membrane is a sufficient trigger of clathrin-mediated synaptic vesicle endocytosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Axons / physiology
  • Brain Stem / physiology
  • Calcium / metabolism*
  • Calcium / pharmacology
  • Cell Membrane / physiology
  • Cell Membrane / ultrastructure
  • Clathrin / metabolism*
  • Coated Pits, Cell-Membrane / physiology*
  • Coated Pits, Cell-Membrane / ultrastructure
  • Electric Stimulation
  • Endocytosis / physiology*
  • Exocytosis / physiology*
  • Lampreys
  • Membrane Potentials / physiology
  • Microscopy, Electron
  • Spinal Cord / drug effects
  • Spinal Cord / physiology*
  • Synapses / drug effects
  • Synapses / physiology*
  • Synapses / ultrastructure
  • Synaptic Vesicles / drug effects
  • Synaptic Vesicles / physiology*
  • Synaptic Vesicles / ultrastructure


  • Clathrin
  • Calcium