title: Functional plasticity triggers formation and pruning of dendritic spines in cultured hippocampal networks.
abstract: Despite widespread interest in dendritic spines, little is known about the mechanisms responsible for spine formation, retraction, or stabilization. We have now found that a brief exposure of cultured hippocampal neurons to a conditioning medium that favors activation of the NMDA receptor produces long-term modification of their spontaneous network activity. The conditioning protocol enhances correlated activity of neurons in the culture, in a process requiring an increase in [Ca(2+)](i) and is associated with both formation of novel dendritic spines and pruning of others. The novel spines are likely to be touched by a presynaptic terminal, labeled with FM4-64 dye, whereas the absence of such terminals increases the likelihood of spine pruning. These results indicate that long-term functional changes are correlated with morphological modifications of dendritic spines of neurons in a network.
authors.affiliation: Department of Neurobiology, The Weizmann Institute, Rehovot 76100, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Goldin
authors.forename: M
authors.initials: M
authors.lastname: Segal
authors.forename: E
authors.initials: E
authors.lastname: Avignone
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D003712:Dendrites / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D005456:Fluorescent Dyes; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009415:Nerve Net / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D011726:Pyridinium Compounds; D000644:Quaternary Ammonium Compounds; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D017077:Culture Media, Conditioned; D018691:Excitatory Amino Acid Antagonists; C092350:FM 4-64; D005456:Fluorescent Dyes; D011726:Pyridinium Compounds; D000644:Quaternary Ammonium Compounds; D016194:Receptors, N-Methyl-D-Aspartate; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D004533:Egtazic Acid; D015763:2-Amino-5-phosphonovalerate