title: GABA-A receptor-dependent mechanisms prevent excessive spine elimination during postnatal maturation of the mouse cortex in vivo.
abstract: Dendritic spine dynamics are implicated in the structural plasticity of cognition-related neuroconnectivity. This study utilized the transcranial in vivo imaging approach to investigate spine dynamics in intact brains of living yellow fluorescent protein-expressing mice. A developmental switch in the net spine loss rate occurred at ∼4 months of age. The initially rapid rate slowed down ∼6-fold due to substantially reduced spine elimination with minor changes in formation. Furthermore, pharmacological blockade of γ-aminobutyric acid type A (GABA-A) receptors resulted in significantly increased elimination of pre-existing spines without affecting new spine formation. Spine elimination returned to normal levels following treatment cessation. Thus, GABA-A receptor-dependent mechanisms act as "brakes" - keeping spine elimination in check to prevent over-pruning, thereby preserving the integrity of cognition-related cortical circuits.
authors.affiliation: Department of Neurobiology and Behavior and Center for Nervous System Disorders, State University of New York at Stony Brook, Stony Brook, NY 11794, United States. Electronic address: yachi.chen@stonybrook.edu.
authors.forename: Yachi
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D049229:Dendritic Spines / Q000378:metabolism*; D006801:Humans; D008297:Male; D051379:Mice; D057054:Molecular Imaging; D019579:Neocortex / Q000166:cytology* / Q000254:growth & development*; D011963:Receptors, GABA-A / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism
chemical_list: D011963:Receptors, GABA-A
keywords: Bicuculline; Cortex; Dendritic spine; Development; GABA-A receptor