Spatiotemporal alterations of cortical network activity by selective loss of NOS-expressing interneurons

Dan Shlosberg, Yossi Buskila, Yasmin Abu-Ghanem, Yael Amitai

Research output: Contribution to journalArticlepeer-review

23 Scopus citations

Abstract

Deciphering the role of GABAergic neurons in large neuronal networks such as the neocortex forms a particularly complex task as they comprise a highly diverse population. The neuronal isoform of the enzyme nitric oxide synthase (nNOS) is expressed in the neocortex by specific subsets of GABAergic neurons. These neurons can be identified in live brain slices by the nitric oxide (NO) fluorescent indicator diaminofluorescein-2 diacetate (DAF-2DA). However, this indicator was found to be highly toxic to the stained neurons. We used this feature to induce acute phototoxic damage to NO-producing neurons in cortical slices, and measured subsequent alterations in parameters of cellular and network activity. Neocortical slices were briefly incubated in DAF-2DA and then illuminated through the 4x objective. Histochemistry for NADPH-diaphorase (NADPH-d), a marker for nNOS activity, revealed elimination of staining in the illuminated areas following treatment. Whole cell recordings from several neuronal types before, during, and after illumination confirmed the selective damage to non-fast-spiking (FS) interneurons. Treated slices displayed mild disinhibition. The reversal potential of compound synaptic events on pyramidal neurons became more positive, and their decay time constant was elongated, substantiating the removal of an inhibitory conductance. The horizontal decay of local field potentials (LFPs) was significantly reduced at distances of 300-400 (im from the stimulation, but not when inhibition was non-selectively weakened with the GABA A blocker picrotoxin. Finally, whereas the depression of LFPs along short trains of 40 Hz stimuli was linearly reduced with distance or initial amplitude in control slices, this ordered relationship was disrupted in DAF-treated slices. These results reveal that NO-producing interneurons in the neocortex convey lateral inhibition to neighboring columns, and shape the spatiotemporal dynamics of the network's activity.

Original languageEnglish
Article number3
JournalFrontiers in Neural Circuits
Issue numberFEBRUARY
DOIs
StatePublished - 20 Feb 2012

Keywords

  • Barrel cortex
  • DAF-2DA
  • Dendritic delay
  • Dendritic inhibition
  • Epilepsy
  • Lateral inhibition
  • Nitric oxide
  • Synaptic integration

ASJC Scopus subject areas

  • Neuroscience (miscellaneous)
  • Sensory Systems
  • Cognitive Neuroscience
  • Cellular and Molecular Neuroscience

Fingerprint

Dive into the research topics of 'Spatiotemporal alterations of cortical network activity by selective loss of NOS-expressing interneurons'. Together they form a unique fingerprint.

Cite this