The glial fascicle: an ontogenic and phylogenic unit guiding, supplying and distributing mammalian cortical neurons.
Neurons destined for the mammalian neocortex migrate along radial glial cells (RGCs). This paper describes a comparative study of RGCs in the mouse, rat, hamster, cat and human fetus, selected as representative species of mammalian evolution. The glial fascicles display constant features throughout these species: they consist of 4-10 RGCs filled with glycogen. The glial fascicle guides and probably supplies metabolites to the migrating neurons and organizes the vertical lamination of the developing neocortical plate. The neuronal-glial unit which consists of the RGCs and their affiliated migrating neurons is conserved throughout the species studied, suggesting a designation as a phylogenic unit.
Gressens
P
P
Service de Neuropédiatrie, University of Louvain Medical School, Brussels, Belgium.
Evrard
P
P
D000818:Animals; D002415:Cats; D002540:Cerebral Cortex / Q000196:embryology* / Q000648:ultrastructure; D006224:Cricetinae; D008322:Mammals / Q000033:anatomy & histology*; D051379:Mice; D009457:Neuroglia / Q000648:ultrastructure*; D009474:Neurons / Q000648:ultrastructure*; D010802:Phylogeny; D051381:Rats