Early development of neuronal activity in the primate hippocampus in utero.

Abstract : Morphological studies suggest that the primate hippocampus develops extensively before birth, but little is known about its functional development. Patch-clamp recordings of hippocampal neurons and reconstruction of biocytin-filled pyramidal cells were performed in slices of macaque cynomolgus fetuses delivered by cesarean section. We found that during the second half of gestation, axons and dendrites of pyramidal cells grow intensively by hundreds of micrometers per day to attain a high level of maturity near term. Synaptic currents appear around midgestation and are correlated with the level of morphological differentiation of pyramidal cells: the first synapses are GABAergic, and their emergence correlates with the growth of apical dendrite into stratum radiatum. A later occurrence of glutamatergic synaptic currents correlates with a further differentiation of the axodendritic tree and the appearance of spines. Relying on the number of dendritic spines, we estimated that hundreds of new glutamatergic synapses are established every day on a pyramidal neuron during the last third of gestation. Most of the synaptic activity is synchronized in spontaneous slow ( approximately 0.1 Hz) network oscillations reminiscent of the giant depolarizing potentials in neonatal rodents. Epileptiform discharges can be evoked by the GABA(A) receptor antagonist bicuculline by the last third of gestation, and postsynaptic GABA(B) receptors contribute to the termination of epileptiform discharges. Comparing the results obtained in primates and rodents, we conclude that the template of early hippocampal network development is conserved across the mammalian evolution but that it is shifted toward fetal life in primate.
Type de document :
Article dans une revue
Journal of Neuroscience, Society for Neuroscience, 2001, 21 (24), pp.9770-81
Liste complète des métadonnées

Littérature citée [64 références]  Voir  Masquer  Télécharger

Contributeur : Roman Tyzio <>
Soumis le : mercredi 19 mai 2010 - 13:55:29
Dernière modification le : jeudi 20 mai 2010 - 08:27:54
Document(s) archivé(s) le : jeudi 16 septembre 2010 - 14:28:11


Fichiers éditeurs autorisés sur une archive ouverte


  • HAL Id : inserm-00484885, version 1
  • PUBMED : 11739585



Roustem Khazipov, Monique Esclapez, Olivier Caillard, Christophe Bernard, Ilgam Khalilov, et al.. Early development of neuronal activity in the primate hippocampus in utero.. Journal of Neuroscience, Society for Neuroscience, 2001, 21 (24), pp.9770-81. 〈inserm-00484885〉



Consultations de la notice


Téléchargements de fichiers