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Reversal and stabilization of synaptic modifications in a developing visual system.

Qiang Zhou·Huizhong W Tao·Mu-ming Poo
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Abstract

Persistent synaptic modifications are essential for experience-dependent refinement of developing circuits. However, in the developing Xenopus retinotectal system, activity-induced synaptic modifications were quickly reversed either by subsequent spontaneous activity in the tectum or by exposure to random visual inputs. This reversal depended on the burst spiking and activation of the N-methyl-D-aspartate subtype of glutamate receptors. Stabilization of synaptic modifications can be achieved by an appropriately spaced pattern of induction stimuli. These findings underscore the vulnerable nature of activity-induced synaptic modifications in vivo and suggest a temporal constraint on the pattern of visual inputs for effective induction of stable synaptic modifications.

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2-Amino-5-phosphonovalerateAnimalsElectric StimulationExcitatory Postsynaptic PotentialsLong-Term PotentiationLong-Term Synaptic DepressionNeuronsOkadaic AcidPatch-Clamp TechniquesPhosphoprotein PhosphatasesPhotic StimulationReceptors, N-Methyl-D-AspartateRetinaRetinal Ganglion CellsSuperior ColliculiSynapsesSynaptic TransmissionVision, OcularVisual PathwaysXenopusJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Qiang Zhou, Huizhong W Tao, Mu-ming Poo. 2003-06-20. Reversal and stabilization of synaptic modifications in a developing visual system.. https://doi.org/10.1126/science.1082212

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