title: Light-induced plasticity of synaptic AMPA receptor composition in retinal ganglion cells.
abstract: Light-evoked responses of all three major classes of retinal ganglion cells (RGCs) are mediated by NMDA receptors (NMDARs) and AMPA receptors (AMPARs). Although synaptic activity at RGC synapses is highly dynamic, synaptic plasticity has not been observed in adult RGCs. Here, using patch-clamp recordings in dark-adapted mouse retina, we report a retina-specific form of AMPAR plasticity. Both chemical and light activation of NMDARs caused the selective endocytosis of GluA2-containing, Ca(2+)-impermeable AMPARs on RGCs and replacement with GluA2-lacking, Ca(2+)-permeable AMPARs. The plasticity was expressed in ON but not OFF RGCs and was restricted solely to the ON responses in ON-OFF RGCs. Finally, the plasticity resulted in a shift in the light responsiveness of ON RGCs. Thus, physiologically relevant light stimuli can induce a change in synaptic receptor composition of ON RGCs, providing a mechanism by which the sensitivity of RGC responses may be modified under scotopic conditions.
authors.affiliation: Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, The Rose F. Kennedy Center, 1410 Pelham Parkway, Bronx, NY 10461, USA. rebecca.jones@phd.einstein.yu.edu
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Jones
authors.forename: Reed C
authors.initials: RC
authors.lastname: Carroll
authors.forename: Scott
authors.initials: S
authors.lastname: Nawy
mesh_terms: D000818:Animals; D019706:Excitatory Postsynaptic Potentials; D008027:Light; D051379:Mice; D008810:Mice, Inbred C57BL; D009473:Neuronal Plasticity / Q000502:physiology*; D018408:Patch-Clamp Techniques; D018091:Receptors, AMPA / Q000378:metabolism*; D012165:Retinal Ganglion Cells / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D018091:Receptors, AMPA