Long-lasting enhanced expression in the rat hippocampus of NMDAR1 splice variants in a kainate model of epilepsy.

Abstract : Chronic epilepsy is associated with increased excitability which may result from abnormal glutamatergic synaptic transmission involving altered properties of N-methyl-D-aspartate (NMDA) receptors. To date two gene families encoding NMDA receptor subunits have been cloned, NR1 and NR2. Eight NR1 mRNAs are generated by alternative splicing of exons 5, 21 and 22; the NR1-1 to NR1-4 C-terminal variants exist in the a or b version depending on the presence or absence of the domain encoded by exon 5. Epilepsy was induced in rats by unilateral intra-amygdalar injection of kainate and animals were killed from 6 h to 4 months following the injection. Increased NR1 mRNA levels were observed during status epilepticus (6-24 h after the injection), both psilateral and contralateral, while a second wave of NMDAR1 mRNA increase occurred in chronic epileptic animals, between 21 days and 4 months following kainate injection. Our data show: (i) a permanent increase of the NR1-2a and NR1-2b mRNA species (containing exon 22) in all hippocampal fields, both ipsilateral and contralateral, and (ii) an increase of the NR1-3 (a and b) mRNAs (containing exon 21) in the ipsilateral CA1, and NR1-3a mRNA in the ipsilateral dentate gyrus. No long-term changes were observed for the NR1-1 and NR14 splice variants. In the ipsilateral CA3 area a globally decreased mRNA expression was associated with neuronal loss. A possible contribution to the maintenance of the epileptic state by an increased expression of NMDA receptors is discussed.
Type de document :
Article dans une revue
European Journal of Neuroscience, Wiley, 1998, 10 (2), pp.497-507
Liste complète des métadonnées

Littérature citée [62 références]  Voir  Masquer  Télécharger

Contributeur : Roman Tyzio <>
Soumis le : jeudi 30 septembre 2010 - 16:12:51
Dernière modification le : vendredi 13 avril 2018 - 01:03:51
Document(s) archivé(s) le : jeudi 30 mars 2017 - 01:49:11


 Accès restreint
Fichier visible le : jamais

Connectez-vous pour demander l'accès au fichier


  • HAL Id : inserm-00522431, version 1
  • PUBMED : 9749712



Amina Rafiki, Yezekiel Ben-Ari, Michel Khrestchatisky, Alfonso Represa. Long-lasting enhanced expression in the rat hippocampus of NMDAR1 splice variants in a kainate model of epilepsy.. European Journal of Neuroscience, Wiley, 1998, 10 (2), pp.497-507. 〈inserm-00522431〉



Consultations de la notice