Changes in D-serine levels and localization during postnatal development of the rat vestibular nuclei.
The patterns of development of the vestibular nuclei (VN) and their main connections involving glutamate neurotransmission offer a good model for studying the function of the glial-derived neuromodulator D-serine in synaptic plasticity. In this study we show that D-serine is present in the VN and we analyzed its distribution and the levels of expression of serine racemase and D-amino acid oxidase (D-AAO) at different stages of postnatal (P) development. From birth to P21, high levels of D-serine were detected in glial cells and processes in all parts of the VN. This period corresponded to high expression of serine racemase and low expression of D-AAO. On the other hand, in the mature VN D-serine displayed very low levels and was mainly localized in neuronal cell bodies and dendrites. This drop of D-serine in adult stages corresponded to an increasing expression of D-AAO at mature stages. High levels of glial D-serine during the first 3 weeks of postnatal development correspond to an intense period of plasticity and synaptogenesis and maturation of VN afferents, suggesting that D-serine could be involved in these phenomena. These results demonstrate for the first time that changes in D-serine levels and distribution occur during postnatal development in the central nervous system. The strong decrease of D-serine levels and the glial-to-neuronal switch suggests that D-serine may have distinct functional roles depending on the developmental stage of the vestibular network.
Puyal
Julien
J
Department of Cell Biology and Morphology, University of Lausanne, 1005 Lausanne, Switzerland. JulienPierre.Puyal@unil.ch
Martineau
Magalie
M
Mothet
Jean-Pierre
JP
Nicolas
Marie-Thérèse
MT
Raymond
Jacqueline
J
D000344:Afferent Pathways / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D015415:Biomarkers / Q000378:metabolism; D002450:Cell Communication / Q000502:physiology*; D002454:Cell Differentiation / Q000502:physiology; D003605:D-Amino-Acid Oxidase / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009457:Neuroglia / Q000378:metabolism*; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D019998:Racemases and Epimerases / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012694:Serine / Q000378:metabolism*; D013237:Stereoisomerism; D009435:Synaptic Transmission / Q000502:physiology; D014726:Vestibular Nuclei / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D000099300:Serine Racemase
D015415:Biomarkers; D003605:D-Amino-Acid Oxidase; D009419:Nerve Tissue Proteins; D019998:Racemases and Epimerases; D012694:Serine; D000099300:Serine Racemase