The Journal of comparative neurology
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We describe the expression of mRNA encoding ligands and receptors of members of the GDNF family and members of the neurotrophin family in the adult human spinal cord and dorsal root ganglia (DRG). Fetal human spinal cord and ganglia were investigated for the presence of ligands and receptors of the neurotrophin family. Tissues were collected from human organ donors and after routine elective abortions. ⋯ Fetal DRG cells were positive for the same probes as adult DRG cells except for NT-3, which was only found in fetal DRG cells. Messenger RNA species only expressed at detectable levels in fetal but not adult spinal cord tissues included GDNF, GFR alpha-2, NT-3, and p75. Notably, GFR alpha-2, which is expressed in the adult rat spinal cord, was not found in the adult human spinal cord.
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Quantitative analysis of ER alpha and GAD colocalization in the hippocampus of the adult female rat.
Despite the many effects of estrogen in the hippocampus, there has been little evidence that hippocampal principal cells express nuclear estrogen receptors. In the hippocampus, the alpha form of the nuclear estrogen receptor (ER alpha) has been localized to sparsely distributed cells with the morphological characteristics of inhibitory interneurons. Because inhibitory neurons may be involved in the effects of estrogen on hippocampal principal cells, quantitative description of ER alpha expression in gamma-aminobutyric acid (GABA)ergic (inhibitory) and non-GABAergic cells of the hippocampus is a key step in understanding the mechanism(s) of estrogen action on hippocampal circuitry. ⋯ Double-labeled cells were concentrated at the border between str. radiatum and str. lacunosum-moleculare. In the ventral hippocampus, we found a very high number of ER alpha-positive cells, the majority of which were not immunoreactive for GAD and are likely to be pyramidal cells. These findings suggest that ER alpha can mediate the effects of estrogen primarily in GABAergic neurons in the dorsal hippocampus and in both GABAergic and non-GABAergic neurons in the ventral hippocampus.