title: Dendritic spine dynamics leading to spine elimination after repeated inductions of LTD.
abstract: Memory is fixed solidly by repetition. However, the cellular mechanism underlying this repetition-dependent memory consolidation/reconsolidation remains unclear. In our previous study using stable slice cultures of the rodent hippocampus, we found long-lasting synaptic enhancement/suppression coupled with synapse formation/elimination after repeated inductions of chemical LTP/LTD, respectively. We proposed these phenomena as useful model systems for analyzing repetition-dependent memory consolidation. Recently, we analyzed the dynamics of dendritic spines during development of the enhancement, and found that the spines increased in number following characteristic stochastic processes. The current study investigates spine dynamics during the development of the suppression. We found that the rate of spine retraction increased immediately leaving that of spine generation unaltered. Spine elimination occurred independent of the pre-existing spine density on the dendritic segment. In terms of elimination, mushroom-type spines were not necessarily more stable than stubby-type and thin-type spines.
authors.affiliation: Laboratory of Synaptic Plasticity, Osaka University Graduate School of Frontier Biosciences, Yamadaoka 1-3, Suita 565-0871 Osaka, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Hasegawa
authors.affiliation: Laboratory of Synaptic Plasticity, Osaka University Graduate School of Frontier Biosciences, Yamadaoka 1-3, Suita 565-0871 Osaka, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Sakuragi
authors.affiliation: Laboratory of Synaptic Plasticity, Osaka University Graduate School of Frontier Biosciences, Yamadaoka 1-3, Suita 565-0871 Osaka, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Tominaga-Yoshino
authors.affiliation: Laboratory of Synaptic Plasticity, Osaka University Graduate School of Frontier Biosciences, Yamadaoka 1-3, Suita 565-0871 Osaka, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Ogura
mesh_terms: D000818:Animals; D049229:Dendritic Spines / Q000187:drug effects / Q000502:physiology*; D005456:Fluorescent Dyes / Q000737:chemistry; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects; D008734:Methoxyhydroxyphenylglycol / Q000031:analogs & derivatives / Q000494:pharmacology; D051379:Mice; D008822:Mice, Transgenic; D018613:Microscopy, Confocal; D013569:Synapses / Q000502:physiology*; D013997:Time Factors
chemical_list: D005456:Fluorescent Dyes; D008734:Methoxyhydroxyphenylglycol; C010117:3,4-dihydroxyphenylglycol