Neurotoxicity Research

, Volume 23, Issue 4, pp 393–400

Excitotoxicity in the Pathogenesis of Autism

  • M. M. Essa
  • N. Braidy
  • K. R. Vijayan
  • S. Subash
  • G. J. Guillemin
Review Article


Autism is a debilitating neurodevelopment disorder characterised by stereotyped interests and behaviours, and abnormalities in verbal and non-verbal communication. It is a multifactorial disorder resulting from interactions between genetic, environmental and immunological factors. Excitotoxicity and oxidative stress are potential mechanisms, which are likely to serve as a converging point to these risk factors. Substantial evidence suggests that excitotoxicity, oxidative stress and impaired mitochondrial function are the leading cause of neuronal dysfunction in autistic patients. Glutamate is the primary excitatory neurotransmitter produced in the CNS, and overactivity of glutamate and its receptors leads to excitotoxicity. The over excitatory action of glutamate, and the glutamatergic receptors NMDA and AMPA, leads to activation of enzymes that damage cellular structure, membrane permeability and electrochemical gradients. The role of excitotoxicity and the mechanism behind its action in autistic subjects is delineated in this review.


Autism Excitotoxicity Glutamatergic receptors Membrane potential Neurotransmitter Ion channel Free radicals 


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • M. M. Essa
    • 1
    • 2
  • N. Braidy
    • 3
  • K. R. Vijayan
    • 1
  • S. Subash
    • 1
  • G. J. Guillemin
    • 2
    • 4
  1. 1.Department of Food Science and NutritionCollege of Agriculture and Marine Sciences, Sultan Qaboos UniversityMuscatOman
  2. 2.Department of PharmacologyFaculty of Medicine, School of Medical Sciences, University of NSWSydneyAustralia
  3. 3.Faculty of Medicine, School of Psychiatry, University of New South WalesSydneyAustralia
  4. 4.Peter Duncan Neuroscience unitSt Vincent’s Centre for Applied Medical Research, St Vincent’s HospitalSydneyAustralia

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