Experimental Brain Research

, Volume 173, Issue 4, pp 623–628 | Cite as

Concentration of amino acid neurotransmitters in the somatosensory cortex of the rat after surgical or functional deafferentation

  • Marie-Hélène Canu
  • Nicolas Treffort
  • Florence Picquet
  • Guy Dubreucq
  • Yann Guerardel
  • Maurice Falempin
Research Article

Abstract

Hindlimb unloading is considered as a model of functional deafferentation, since in this situation the tactile information from the paw and the proprioceptive input from the limb are dramatically reduced. Unloading induces a shrinkage of the cortical representation of the affected body part associated to a reorganization of topographic maps and to an expansion of receptive fields. Previous studies have suggested that cortical plasticity was the result of a change in the balance of excitation and inhibition in the cortex. The aim of the present study was thus to determine whether deafferentation of the hindlimb representation in the somatosensory cortex, by 14 days of unloading or by surgical means (selective dorsal rhizotomy during 17 days), can change the concentration in various amino acid neurotransmitters in the deprived cortex. The present findings indicate that both types of deafferentation result in a decrease in inhibitory amino acids (GABA, taurine) without significant changes in the main excitatory amino acid (glutamate). In conclusion, the present results support the idea that cortical changes are more likely due to a release from inhibition than to an increased excitation.

Keywords

Hindlimb unloading Rhizotomy Cortical plasticity Glutamate GABA 

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Marie-Hélène Canu
    • 1
  • Nicolas Treffort
    • 1
  • Florence Picquet
    • 1
  • Guy Dubreucq
    • 2
  • Yann Guerardel
    • 3
  • Maurice Falempin
    • 1
  1. 1.Unité de Neurosciences et Physiologie Adaptative, Groupe “Plasticité Neuromusculaire”Université des Sciences et Technologies de LilleVilleneuve d’Ascq CedexFrance
  2. 2.BiodexSt Amand-les-EauxFrance
  3. 3.Laboratoire de Glycobiologie Structurale et Fonctionnelle, UMR CNRS 8576Université des Sciences et Technologies de LilleVilleneuve d’Ascq CedexFrance

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