title: Signaling via dopamine D1 and D3 receptors oppositely regulates cocaine-induced structural remodeling of dendrites and spines.
abstract: Repeated exposure to cocaine can induce persistent alterations in the brain. The structural remodeling of dendrites and dendritic spines is thought to play a critical role in cocaine addiction. We previously demonstrated that signaling via dopamine D1 and D3 receptors have opposite effects on cocaine-induced gene expression. Here, we show that cocaine-induced structural remodeling in the nucleus accumbens (NAc) and caudoputamen (CPu) is mediated by D1 receptors and inhibited by D3 receptors. In addition, chronic exposure to cocaine results in an altered number of asymmetric spine synapses via the actions of both D1 and D3 receptors. The contradictory effects of D1 and D3 receptor signaling on cocaine-induced structural remodeling is associated with NMDA-receptor R1 subunit (NR1) phosphorylation, and is dependent upon the activation of extracellular signal-regulated kinase (ERK). In addition, we found that D1 and D3 receptor signaling has contradictory effects upon the activation of the myocyte enhancer factor 2 (MEF2), which is involved in the dendritic remodeling after cocaine treatment. Together, these data suggest that dopamine D1 and D3 receptors differentially regulate the cocaine-induced structural remodeling of dendrites and spines via mechanisms involving the consecutive actions of NR1 phosphorylation, ERK activation, and MEF2 activity in the NAc and CPu.
authors.affiliation: Department of Pathophysiology, Southern Medical University, Guangzhou, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Nuyun
authors.initials: N
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.forename: Jingjing
authors.initials: J
authors.lastname: Gu
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Zhitao
authors.initials: Z
authors.lastname: Zhou
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D003042:Cocaine / Q000494:pharmacology*; D003712:Dendrites / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D049229:Dendritic Spines / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D005260:Female; D008297:Male; D051379:Mice; D051381:Rats; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors / Q000502:physiology*; D050637:Receptors, Dopamine D3 / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
chemical_list: D017447:Receptors, Dopamine D1; D050637:Receptors, Dopamine D3; D003042:Cocaine