Emergence of coordinated plasticity in the cochlear nucleus and cerebellum.
Synapses formed by one cell type onto another cell type tend to show characteristic short-term plasticity, which varies from facilitating to depressing depending on the particular system. Within a population of synapses, plasticity can also be variable, and it is unknown how this plasticity is determined on a cell-by-cell level. We have investigated this in the mouse cochlear nucleus, where auditory nerve (AN) fibers contact bushy cells (BCs) at synapses called "endbulbs of Held." Synapses formed by different AN fibers onto one BC had plasticity that was more similar than would be expected at random. Experiments using MK-801 indicated that this resulted in part from similarity in the presynaptic probability of release. The similarity was not present in immature synapses but emerged after the onset of hearing. In addition, the phenomenon occurred at excitatory synapses in the cerebellum. This indicates that postsynaptic cells coordinate the plasticity of their inputs, which suggests that plasticity is of fundamental importance to synaptic function.
Department of Biological Sciences, University at Buffalo, State University of New York, Buffalo, New York 14260, USA.
Hua
H
Yang
Matthew A
MA
Xu-Friedman
D000465:Algorithms; D000818:Animals; D002531:Cerebellum / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology*; D003056:Cochlear Nerve / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D005260:Female; D006309:Hearing / Q000502:physiology; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D009412:Nerve Fibers / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D017661:Receptors, Presynaptic / Q000187:drug effects / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology
D018691:Excitatory Amino Acid Antagonists; D017661:Receptors, Presynaptic; D016291:Dizocilpine Maleate