Visual Deprivation During the Critical Period Enhances Layer 2/3 GABAergic Inhibition in Mouse V1

J Neurosci. 2016 Jun 1;36(22):5914-9. doi: 10.1523/JNEUROSCI.0051-16.2016.

Abstract

The role of GABAergic signaling in establishing a critical period for experience in visual cortex is well understood. However, the effects of early experience on GABAergic synapses themselves are less clear. Here, we show that monocular deprivation (MD) during the adolescent critical period produces marked enhancement of GABAergic signaling in layer 2/3 of mouse monocular visual cortex. This enhancement coincides with a weakening of glutamatergic inputs, resulting in a significant reduction in the ratio of excitation to inhibition. The potentiation of GABAergic transmission arises from both an increased number of inhibitory synapses and an enhancement of presynaptic GABA release from parvalbumin- and somatostatin-expressing interneurons. Our results suggest that augmented GABAergic inhibition contributes to the experience-dependent regulation of visual function.

Significance statement: Visual experience shapes the synaptic organization of cortical circuits in the mouse brain. Here, we show that monocular visual deprivation enhances GABAergic synaptic inhibition in primary visual cortex. This enhancement is mediated by an increase in both the number of postsynaptic GABAergic synapses and the probability of presynaptic GABA release. Our results suggest a contributing mechanism to altered visual responses after deprivation.

Keywords: gephyrin; interneuron; monocular deprivation; optogenetics.

Publication types

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

MeSH terms

  • Age Factors
  • Animals
  • Animals, Newborn
  • Channelrhodopsins
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Female
  • Functional Laterality
  • GABAergic Neurons / physiology*
  • In Vitro Techniques
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neural Inhibition / genetics
  • Neural Inhibition / physiology*
  • Parvalbumins / genetics
  • Parvalbumins / metabolism
  • Patch-Clamp Techniques
  • Sensory Deprivation / physiology*
  • Synapses / drug effects
  • Synapses / genetics
  • Synapses / physiology*
  • Synaptic Potentials / drug effects
  • Synaptic Potentials / genetics
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Visual Cortex / cytology*
  • Visual Cortex / growth & development
  • Visual Pathways / physiology*

Substances

  • Channelrhodopsins
  • DNA-Binding Proteins
  • Grhl3 protein, mouse
  • Parvalbumins
  • Transcription Factors