Response features of parvalbumin-expressing interneurons suggest precise roles for subtypes of inhibition in visual cortex

Neuron. 2010 Sep 9;67(5):847-57. doi: 10.1016/j.neuron.2010.08.006.

Abstract

Inhibitory interneurons in the cerebral cortex include a vast array of subtypes, varying in their molecular signatures, electrophysiological properties, and connectivity patterns. This diversity suggests that individual inhibitory classes have unique roles in cortical circuits; however, their characterization to date has been limited to broad classifications including many subtypes. We used the Cre/LoxP system, specifically labeling parvalbumin(PV)-expressing interneurons in visual cortex of PV-Cre mice with red fluorescent protein (RFP), followed by targeted loose-patch recordings and two-photon imaging of calcium responses in vivo to characterize the visual receptive field properties of these cells. Despite their relative molecular and morphological homogeneity, we find that PV+ neurons have a diversity of feature-specific visual responses that include sharp orientation and direction-selectivity, small receptive fields, and band-pass spatial frequency tuning. These results suggest that subsets of parvalbumin interneurons are components of specific cortical networks and that perisomatic inhibition contributes to the generation of precise response properties.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Biophysics
  • Calcium / metabolism
  • Electric Stimulation / methods
  • Glutamate Decarboxylase / genetics
  • Green Fluorescent Proteins / genetics
  • Interneurons / classification*
  • Interneurons / physiology*
  • Luminescent Proteins / genetics
  • Membrane Potentials / physiology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neural Inhibition / physiology*
  • Parvalbumins / metabolism*
  • Patch-Clamp Techniques / methods
  • Photic Stimulation / methods
  • Photons
  • Red Fluorescent Protein
  • Visual Cortex / cytology*
  • Visual Pathways / physiology
  • gamma-Aminobutyric Acid / metabolism

Substances

  • Luminescent Proteins
  • Parvalbumins
  • Green Fluorescent Proteins
  • gamma-Aminobutyric Acid
  • Glutamate Decarboxylase
  • glutamate decarboxylase 1
  • Calcium