GABA vesicles at synapses: Are there 2 distinct pools?

Academic Article

Abstract

  • Fast synaptic inhibition in the neocortex is mediated by the neurotransmitter GABA, acting on GABA A receptors. Neurotransmitters, including GABA, are stored in synaptic vesicles at presynaptic nerve terminals. A long-held assumption has been that evoked and spontaneous neurotransmissions draw on the same pools of vesicles. We review the evidence from FM1-43 studies supporting the contention that at least 2 distinct pools of GABA vesicles are present at inhibitory synapses in the rat neocortex. FM1-43 uptake during spontaneous vesicle endocytosis labels a vesicle pool within neocortical inhibitory nerve terminals that is released much more slowly (ĝ€reluctantĝ€ pool) than those vesicles loaded by electrical stimulation of afferent fibers or hyperkalemic solutions. These multiple pools may play diverse roles in such processes as long-term depression and/or potentiating of inhibitory synaptic transmission, homeostatic plasticity of inhibitory activity, or developmental changes in inhibitory synaptic transmission. © 2009 SAGE Publications.
  • Digital Object Identifier (doi)

    Author List

  • Hablitz JJ; Mathew SS; Pozzo-Miller L
  • Start Page

  • 218
  • End Page

  • 224
  • Volume

  • 15
  • Issue

  • 3