TY - JOUR T1 - Differential Modulation of Drug-Induced Structural and Functional Plasticity of Dendritic Spines JF - Molecular Pharmacology JO - Mol Pharmacol SP - 333 LP - 343 DO - 10.1124/mol.112.078162 VL - 82 IS - 2 AU - Eric C. Miller AU - Lei Zhang AU - Benjamin W. Dummer AU - Desmond R. Cariveau AU - Horace Loh AU - Ping-Yee Law AU - Dezhi Liao Y1 - 2012/08/01 UR - http://molpharm.aspetjournals.org/content/82/2/333.abstract N2 - Drug-induced plasticity of excitatory synapses has been proposed to be the cellular mechanism underlying the aberrant learning associated with addiction. Exposure to various drugs of abuse causes both morphological plasticity of dendritic spines and functional plasticity of excitatory synaptic transmission. Chronic activation of μ-opioid receptors (MOR) in cultured hippocampal neurons causes two forms of synaptic plasticity: loss of dendritic spines and loss of synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. With use of live imaging, patch-clamp electrophysiology, and immunocytochemistry, the present study reveals that these two forms of synaptic plasticity are mediated by separate, but interactive, intracellular signaling cascades. The inhibition of Ca2+/calmodulin-dependent protein kinase II with 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-l-tyrosyl]-4-phenylpiperazine (KN-62) blocks MOR-mediated structural plasticity of dendritic spines, but not MOR-mediated cellular redistribution of GluR1 and GluR2 AMPA receptor subunits. In contrast, the inhibition of calcineurin with tacrolimus (FK506) blocks both cellular processes. These findings support the idea that drug-induced structural and functional plasticity of dendritic spines is mediated by divergent, but interactive, signaling pathways. ER -