Inhibitory Synapses Are Repeatedly Assembled and Removed at Persistent Sites In Vivo

Neuron. 2016 Feb 17;89(4):756-69. doi: 10.1016/j.neuron.2016.01.010. Epub 2016 Feb 4.


Older concepts of a hard-wired adult brain have been overturned in recent years by in vivo imaging studies revealing synaptic remodeling, now thought to mediate rearrangements in microcircuit connectivity. Using three-color labeling and spectrally resolved two-photon microscopy, we monitor in parallel the daily structural dynamics (assembly or removal) of excitatory and inhibitory postsynaptic sites on the same neurons in mouse visual cortex in vivo. We find that dynamic inhibitory synapses often disappear and reappear again in the same location. The starkest contrast between excitatory and inhibitory synapse dynamics is on dually innervated spines, where inhibitory synapses frequently recur while excitatory synapses are stable. Monocular deprivation, a model of sensory input-dependent plasticity, shortens inhibitory synapse lifetimes and lengthens intervals to recurrence, resulting in a new dynamic state with reduced inhibitory synaptic presence. Reversible structural dynamics indicate a fundamentally new role for inhibitory synaptic remodeling--flexible, input-specific modulation of stable excitatory connections.

Publication types

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

MeSH terms

  • Animals
  • Carrier Proteins / metabolism
  • Disks Large Homolog 4 Protein
  • Female
  • Functional Laterality
  • Guanylate Kinases / genetics
  • Guanylate Kinases / metabolism
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Male
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neural Inhibition / genetics
  • Neural Inhibition / physiology*
  • Neuronal Plasticity / physiology*
  • Organ Culture Techniques
  • Pregnancy
  • Pyramidal Cells / ultrastructure*
  • Sensory Deprivation
  • Synapses / physiology*
  • Synapses / ultrastructure
  • Synaptic Transmission / physiology*
  • Visual Cortex / cytology*
  • gamma-Aminobutyric Acid / pharmacology


  • Carrier Proteins
  • Disks Large Homolog 4 Protein
  • Dlg4 protein, mouse
  • Luminescent Proteins
  • Membrane Proteins
  • gephyrin
  • gamma-Aminobutyric Acid
  • Guanylate Kinases