Development of thalamocortical projections in the South American gray short-tailed opossum (Monodelphis domestica)

Détails

ID Serval
serval:BIB_741E4D2DDEE6
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Development of thalamocortical projections in the South American gray short-tailed opossum (Monodelphis domestica)
Périodique
Journal of Comparative Neurology
Auteur(s)
Molnar  Z., Knott  G. W., Blakemore  C., Saunders  N. R.
ISSN
0021-9967 (Print)
Statut éditorial
Publié
Date de publication
09/1998
Volume
398
Numéro
4
Pages
491-514
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Sep 7
Résumé
We determined the time-course and general pattern of thalamocortical development of Monodelphis domestica by tracing projections with carbocyanine dye in fixed postnatal brains between postnatal day 2 (P2) and P30. By P2, the first neurons have migrated to form the preplate of the lateral cortex and have sent out axons into the intermediate zone. By P3, fibers from the preplate of more dorsal cortex have entered the intermediate zone, and, by P5, they reach the primitive internal capsule. Crystal placements in the dorsal thalamus at P2-P3 reveal thalamic axons extending down through the diencephalon and growing out through the internal capsule among groups of back-labelled cells that already project into the thalamus. Thalamic axons arrive at the cortex after the arrival of cells of the true cortical plate has split the preplate into marginal zone and subplate. Axons from the ventral part of the dorsal thalamus reach the lateral cortex by P5: Dorsal thalamic fibers arrive at the extreme dorsal cortex by P9. The deeper layers of the cortex appear to mature relatively earlier in Monodelphis than in eutherian mammals, and the subplate becomes less distinct. Thalamic fibers and their side branches proceed into the cortex without an obvious period of waiting in the subplate, but they do not penetrate the dense cortical plate itself. Monodelphis could provide an excellent model species, because the development of its thalamocortical connections is entirely an extrauterine process: The period P0-P15 corresponds to that of E12-P0 in the rat.
Mots-clé
Animals Animals, Newborn Axons/physiology *Brain Mapping Cerebral Cortex/growth & development/*physiology Opossums/growth & development/*physiology Prosencephalon/physiology Thalamus/growth & development/*physiology
Pubmed
Web of science
Création de la notice
24/01/2008 15:26
Dernière modification de la notice
03/03/2018 18:20
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