The kinetics of synaptic vesicle recycling measured at single presynaptic boutons

Neuron. 1993 Oct;11(4):713-24. doi: 10.1016/0896-6273(93)90081-2.


We used the fluorescent membrane probe FM 1-43 to label recycling synaptic vesicles within the presynaptic boutons of dissociated hippocampal neurons in culture. Quantitative time-lapse fluorescence imaging was employed in combination with rapid superfusion techniques to study the dynamics of synaptic vesicles within single boutons. This approach enabled us to measure exocytosis and to analyze the kinetics of endocytosis and the preparation of endocytosed vesicles for re-release (repriming). Our measurements indicate that under sustained membrane depolarization, endocytosis persists much longer than exocytosis, with a t1/2 approximately 60 s (approximately 24 degrees C); once internalized, vesicles become reavailable for exocytosis in approximately 30 s. Furthermore, we have shown that endocytosis is not dependent on membrane potential and, unlike exocytosis, that it is independent of extracellular Ca2+.

Publication types

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

MeSH terms

  • Animals
  • Cells, Cultured
  • Endocytosis
  • Exocytosis
  • Fluorescent Antibody Technique
  • Fluorescent Dyes
  • Hippocampus / cytology
  • Hippocampus / physiology
  • Hippocampus / ultrastructure
  • Kinetics
  • Membrane Potentials
  • Neurons / physiology*
  • Neurons / ultrastructure
  • Presynaptic Terminals / physiology*
  • Presynaptic Terminals / ultrastructure*
  • Pyramidal Tracts / cytology
  • Pyramidal Tracts / physiology
  • Pyramidal Tracts / ultrastructure
  • Pyridinium Compounds*
  • Quaternary Ammonium Compounds*
  • Rats
  • Rats, Sprague-Dawley
  • Synapsins / analysis
  • Synaptic Vesicles / physiology*
  • Synaptic Vesicles / ultrastructure*


  • FM1 43
  • Fluorescent Dyes
  • Pyridinium Compounds
  • Quaternary Ammonium Compounds
  • Synapsins