Intermediate zone cells express @entity460 -permeable XXXX receptors and establish close contact with growing axons.

@entity2227 @entity19 @entity140 @entity143 @entity460 @entity1953 @entity9449
Recent studies have shown that cells in the intermediate zone (IZ) of the embryonic neocortex originate in the basal telencephalon and migrate tangentially in the cortical wall (;; ). We had previously observed growing cortical axons closely apposed to calbindin-positive, tangentially oriented cells in the IZ (), and it has been shown that neurites in the IZ express a @entity2227 transporter (). To test if @entity2227 released by corticofugal growth cones could influence the tangential IZ cells, we characterized the @entity2227 receptors expressed by IZ cells using patch-clamp techniques, histochemical labeling, and immunostaining on slices of embryonic @entity19 forebrain. We show that tangential IZ cells express inwardly rectifying kainate responses, but not @entity143 responses, and accumulate @entity1953 after @entity140 receptor activation. We conclude that IZ cells express @entity460 -permeable @entity140 receptors. This property correlates with our observation that the @entity9449 subunit is not expressed in the IZ. @entity140 receptors are activated by a millimolar concentration of @entity2227 . To know whether this high level of @entity2227 could occur at the surface of IZ cells, we examined contacts made by corticofugal growth cones and calbindin-positive IZ cells using electron microscopy. We show vesicle-containing neurites tightly apposed to calbindin-positive IZ cells over remarkably long length. This suggests that @entity2227 released by growing corticofugal axons could reach high concentrations close to @entity140 receptors of tangential IZ cells and efficiently activate them to control the intracellular @entity460 in embryonic IZ cells.
