Szh. Naqui et al., The noradrenergic system influences the fate of Cajal-Retzius cells in thedeveloping cerebral cortex, DEV BRAIN R, 113(1-2), 1999, pp. 75-82
Cajal-Retzius cells are neurons prominently located in layer I of the devel
oping cerebral cortex. They are the first neurons to be born in the cortex
reaching maturity long before any other cortical neuronal cell type; later
in development they degenerate and/or change phenotype. The noradrenergic s
ystem, which originates in the locus coeruleus in the brain stem, is one of
the earliest axonal systems to enter the cortex forming contacts with Caja
l-Retzius cells in layer I. Here we followed the course of development of t
he Cajal-Retzius cells in postnatal life in animals depleted of noradrenali
ne in the cortex. We found that removal of this system after birth resulted
in significantly more Cajal-Retzius cells during the first 2 weeks of life
. This may be due to the observed decline in the number of dying cells in l
ayer I of these animals during the same period. We speculate that the norad
renergic system regulates the development of Cajal-Retzius cells which have
been implicated in neuronal migration and laminar formation in the cerebra
l cortex. (C) 1999 Elsevier Science B.V. All rights reserved.