d-Serine as a Neuromodulator: Regional and Developmental Localizations in Rat Brain Glia Resemble NMDA Receptors

摘要: D-Serine is localized in mammalian brain to a discrete population of glial cells near NMDA receptors, suggesting that D-serine an endogenous agonist the receptor-associated glycine site. To explore this possibility, we have compared immunohistochemical localizations D-serine, glycine, and receptors rat brain. In telencephalon, concentrated protoplasmic astrocytes, which are abundant neuropil close vicinity receptor 2A/B subunits. Ultrastructural examination CA1 region hippocampus reveals cytosolic matrix astrocytes ensheath neurons blood vessels, whereas NR2A/B dendritic spines. By contrast, immunoreactivity telencephalon lowest During postnatal week 2, levels cerebellum comparable those adult cerebral cortex but fall undetectable by day 26. observe parallel ontogeny Bergmann glia Purkinje cells, role for astrocytic receptor-mediated synaptogenesis. radial processes also well positioned regulate receptor-dependent granule cell migration. inner layer, found transiently surrounding glomeruli, where it could development mossy fiber/granule synapse. seems be ligand sites developing cerebellum, predominates olfactory bulb, hindbrain.