title: Glial protein S100B modulates long-term neuronal synaptic plasticity.
abstract: Glial cells are traditionally regarded as elements for structural support and ionic homeostasis, but have recently attracted attention as putative integral elements of the machinery involved in synaptic transmission and plasticity. Here, we demonstrate that calcium-binding protein S100B, which is synthesized in considerable amounts in astrocytes (a major glial cell subtype), modulates long-term synaptic plasticity. Mutant mice devoid of S100B developed normally and had no detectable abnormalities in the cytoarchitecture of the brain. These mutant mice, however, had strengthened synaptic plasticity as identified by enhanced long-term potentiation (LTP) in the hippocampal CA1 region. Perfusion of hippocampal slices with recombinant S100B proteins reversed the levels of LTP in the mutant slices to those of the wild-type slices, indicating that S100B might act extracellularly. In addition to enhanced LTP, mutant mice had enhanced spatial memory in the Morris water maze test and enhanced fear memory in the contextual fear conditioning. The results indicate that S100B is a glial modulator of neuronal synaptic plasticity and strengthen the notion that glial-neuronal interaction is important for information processing in the brain.
authors.affiliation: Laboratories for Behavioral Genetics and Neuronal Circuit Dynamics, and Neuronal Circuit Mechanisms Research Group, Brain Science Institute (BSI), Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishiyama
authors.forename: Thomas
authors.initials: T
authors.lastname: Knopfel
authors.forename: Shogo
authors.initials: S
authors.lastname: Endo
authors.forename: Shigeyoshi
authors.initials: S
authors.lastname: Itohara
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D003213:Conditioning, Psychological / Q000187:drug effects; D005239:Fear / Q000187:drug effects / Q000502:physiology; D017353:Gene Deletion; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D009414:Nerve Growth Factors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D013028:Space Perception / Q000187:drug effects / Q000502:physiology; D013569:Synapses / Q000187:drug effects / Q000502:physiology*
chemical_list: D002135:Calcium-Binding Proteins; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579159:S100b protein, mouse; D002118:Calcium