Structural plasticity of dentate granule cell mossy fibers during the development of limbic epilepsy.

Published

Journal Article

Altered granule cell>CA3 pyramidal cell synaptic connectivity may contribute to the development of limbic epilepsy. To explore this possibility, granule cell giant mossy fiber bouton plasticity was examined in the kindling and pilocarpine models of epilepsy using green fluorescent protein-expressing transgenic mice. These studies revealed significant increases in the frequency of giant boutons with satellite boutons 2 days and 1 month after pilocarpine status epilepticus, and increases in giant bouton area at 1 month. Similar increases in giant bouton area were observed shortly after kindling. Finally, both models exhibited plasticity of mossy fiber giant bouton filopodia, which contact GABAergic interneurons mediating feedforward inhibition of CA3 pyramids. In the kindling model, however, all changes were fleeting, having resolved by 1 month after the last evoked seizure. Together, these findings demonstrate striking structural plasticity of granule cell mossy fiber synaptic terminal structure in two distinct models of adult limbic epileptogenesis. We suggest that these plasticities modify local connectivities between individual mossy fiber terminals and their targets, inhibitory interneurons, and CA3 pyramidal cells potentially altering the balance of excitation and inhibition during the development of epilepsy.

Full Text

Duke Authors

Cited Authors

  • Danzer, SC; He, X; Loepke, AW; McNamara, JO

Published Date

  • January 2010

Published In

Volume / Issue

  • 20 / 1

Start / End Page

  • 113 - 124

PubMed ID

  • 19294647

Pubmed Central ID

  • 19294647

Electronic International Standard Serial Number (EISSN)

  • 1098-1063

Digital Object Identifier (DOI)

  • 10.1002/hipo.20589

Language

  • eng

Conference Location

  • United States