title: Long-Term Spatiotemporal Reconfiguration of Neuronal Activity Revealed by Voltage-Sensitive Dye Imaging in the Cerebellar Granular Layer.
abstract: Understanding the spatiotemporal organization of long-term synaptic plasticity in neuronal networks demands techniques capable of monitoring changes in synaptic responsiveness over extended multineuronal structures. Among these techniques, voltage-sensitive dye imaging (VSD imaging) is of particular interest due to its good spatial resolution. However, improvements of the technique are needed in order to overcome limits imposed by its low signal-to-noise ratio. Here, we show that VSD imaging can detect long-term potentiation (LTP) and long-term depression (LTD) in acute cerebellar slices. Combined VSD imaging and patch-clamp recordings revealed that the most excited regions were predominantly associated with granule cells (GrCs) generating EPSP-spike complexes, while poorly responding regions were associated with GrCs generating EPSPs only. The correspondence with cellular changes occurring during LTP and LTD was highlighted by a vector representation obtained by combining amplitude with time-to-peak of VSD signals. This showed that LTP occurred in the most excited regions lying in the core of activated areas and increased the number of EPSP-spike complexes, while LTD occurred in the less excited regions lying in the surround. VSD imaging appears to be an efficient tool for investigating how synaptic plasticity contributes to the reorganization of multineuronal activity in neuronal circuits.
authors: Dipartimento di Scienze del Sistema Nervoso e del Comportamento, Università di Pavia, 27100 Pavia, Italy.
authors: Daniela
authors: D
authors: Gandolfi
authors: Dipartimento di Scienze del Sistema Nervoso e del Comportamento, Università di Pavia, 27100 Pavia, Italy ; Dipartimento di Scienze Biomediche, Metaboliche e Neuroscienze, Università di Modena e Reggio Emilia, 41125 Modena, Italy.
authors: Jonathan
authors: J
authors: Mapelli
authors: Dipartimento di Scienze del Sistema Nervoso e del Comportamento, Università di Pavia, 27100 Pavia, Italy ; Brain Connectivity Center, C. Mondino National Neurological Institute, 27100 Pavia, Italy.
authors: Egidio
authors: E
authors: D'Angelo
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000166:cytology / Q000502:physiology*; D003594:Cytoplasmic Granules / Q000502:physiology; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000502:physiology; D009415:Nerve Net / Q000502:physiology; D059906:Neuroimaging / Q000379:methods*; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D059629:Signal-To-Noise Ratio; D056969:Voltage-Sensitive Dye Imaging