Pathway-specific trafficking of native AMPARs by in vivo experience.
An accumulating body of evidence supports the notion that trafficking of AMPA receptors (AMPARs) underlies strengthening of glutamatergic synapses and, in turn, learning and memory in the behaving animal. However, without exception, these experiments have been performed using artificial stimulation protocols, cultured neurons, or viral-overexpression systems that can significantly alter the normal function of AMPARs. Using a single-whisker experience protocol that significantly enhances neuronal responses in vivo, we have targeted neurons in and around the spared whisker column of fosGFP transgenic mice for whole-cell recording. Here we show that in vivo experience induces the pathway-specific strengthening of neocortical excitatory synapses. By assaying AMPARs for rectification and sensitivity to joro spider toxin, we find that in vivo experience induces the delivery of native GluR2-lacking receptors at spared, but not deprived, inputs. These data demonstrate that pathway-specific trafficking of GluR2-lacking AMPARs is a normal feature of synaptic strengthening that underlies experience-dependent plasticity in the behaving animal.
Clem
Roger L
RL
Department of Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Barth
Alison
A
D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D049452:Green Fluorescent Proteins / Q000235:genetics; D066298:In Vitro Techniques; D051379:Mice; D008822:Mice, Transgenic; D019579:Neocortex / Q000166:cytology; D009434:Neural Pathways / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D016761:Oncogene Proteins v-fos / Q000378:metabolism; D018408:Patch-Clamp Techniques / Q000379:methods; D021381:Protein Transport / Q000502:physiology; D018091:Receptors, AMPA / Q000378:metabolism*; D013569:Synapses / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D014738:Vibrissae / Q000294:innervation* / Q000502:physiology
D016761:Oncogene Proteins v-fos; D018091:Receptors, AMPA; D049452:Green Fluorescent Proteins; D002118:Calcium