title: Bidirectional activity-dependent morphological plasticity in hippocampal neurons.
abstract: Dendritic spines on pyramidal neurons receive the vast majority of excitatory input and are considered electrobiochemical processing units, integrating and compartmentalizing synaptic input. Following synaptic plasticity, spines can undergo morphological plasticity, which possibly forms the structural basis for long-term changes in neuronal circuitry. Here, we demonstrate that spines on CA1 pyramidal neurons from organotypic slice cultures show bidirectional activity-dependent morphological plasticity. Using two-photon time-lapse microscopy, we observed that low-frequency stimulation induced NMDA receptor-dependent spine retractions, whereas theta burst stimulation led to the formation of new spines. Moreover, without stimulation the number of spine retractions was on the same order of magnitude as the stimulus-induced spine gain or loss. Finally, we found that the ability of neurons to eliminate spines in an activity-dependent manner decreased with developmental age. Taken together, our data show that hippocampal neurons can undergo bidirectional morphological plasticity; spines are formed and eliminated in an activity-dependent way.
authors.affiliation: Max-Planck-Institute of Neurobiology, Am Klopferspitz 18, 82152 München-Martinsried, Germany.
authors.forename: U Valentin
authors.initials: UV
authors.lastname: Nägerl
authors.forename: Nicola
authors.initials: N
authors.lastname: Eberhorn
authors.forename: Sidney B
authors.initials: SB
authors.lastname: Cambridge
authors.forename: Tobias
authors.initials: T
authors.lastname: Bonhoeffer
mesh_terms: D000818:Animals; D016922:Cellular Senescence / Q000502:physiology; D049229:Dendritic Spines / Q000502:physiology / Q000648:ultrastructure; D004558:Electric Stimulation / Q000379:methods; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D066298:In Vitro Techniques; D051379:Mice; D008822:Mice, Transgenic; D009473:Neuronal Plasticity / Q000502:physiology*; D017966:Pyramidal Cells / Q000502:physiology* / Q000648:ultrastructure*; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate