Expression of ARVCF in the Human Ganglionic Eminence during Fetal Development

ARVCF (armadillo repeat gene deleted in velocardiofacial syndrome) is a recently characterized member of the catenin p120 (ctn) subfamily of the armadillo repeat proteins. It is involved in modulation of cell-cell adhesion essential to many developmental processes including cellular rearrangement and migration. In the present study, by using specific immunohistochemical methods, strongly ARVCF-immunoreactive cells in a high packing density were found in the human ganglionic eminence (GE), a telencephalic structure which gives rise to precursor neurons of the striatum, the amygdala and the basal nucleus of Meynert. From 20 to 25 weeks of gestation, stripes of immunoreactive cells were found to extend from both the superior part of the GE towards the intermediate zone of the neocortex and from the inferior part of the GE either towards the amygdaloid complex or more laterally towards the intermediate zone. Bands of ARVCF-positive cells were also identified in the gangliothalamic body, a transient target for the migrating neurons from the GE to the thalamus. Double immunolabelling with ARVCF and calretinin antibodies, which mark the GE neurons migrating towards the cerebral cortex, revealed that a majority of ARVCF-positive neurons at the periphery of the GE and the cellular extensions from the GE also expressed calretinin. Our results implicate a very close association of ARVCF with migrating neurons from the GE.

Expression of connexin 26 in the ganglionic eminence of preterm infants after bleedings

The ganglionic eminence being a prominent part of the telencephalic proliferative zone is the most common site of bleedings in preterm infants. This immunohistochemical study demonstrates that connexin 26 involved in forming intercellular gap junctions is expressed in ganglionic eminence cells up to 500 microm from the bleeding. In controls, no positive cells are present. It is discussed that an increase of gap junctional communication may result in spreading of the primary injury.