The role of actin in the regulation of dendritic spine morphology and bidirectional synaptic plasticity.
Dendritic spines, which are the preferred site of excitatory synapses in the mammalian CNS, are actin-rich structures. We hypothesized that dynamic regulation of actin in spines would differentially affects processes that lead to potentiation vs depression of synaptic efficacy. Here, we report that the expression of long-term depression of excitatory synaptic transmission persists in the presence of actin polymerization in rat hippocampal slices. We observe that the reversal of LTD, de-depression, by high-frequency stimulation was completely blocked. Using electron microscopy, dramatic changes in dendritic spine morphology which accompany the sustained, irreversible depression of excitatory synaptic transmission were observed.
Chen
Yucui
Y
Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
Bourne
Jennifer
J
Pieribone
Vincent A
VA
Fitzsimonds
Reiko Maki
RM
D000199:Actins / Q000502:physiology*; D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D015638:Cytochalasin D / Q000494:pharmacology; D003712:Dendrites / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D004558:Electric Stimulation / Q000379:methods; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D006624:Hippocampus / Q000502:physiology / Q000648:ultrastructure; D066298:In Vitro Techniques; D008297:Male; D008854:Microscopy, Electron / Q000379:methods; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects / Q000648:ultrastructure; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013569:Synapses / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines
D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D019384:Nucleic Acid Synthesis Inhibitors; D013844:Thiazoles; D053778:Thiazolidines; D015638:Cytochalasin D; C037068:latrunculin B