title: Distinct roles of dopamine D3 receptors in modulating methamphetamine-induced behavioral sensitization and ultrastructural plasticity in the shell of the nucleus accumbens.
abstract: Persistent changes in behavior and psychological function that occur as a consequence of exposure to drugs of abuse are thought to be mediated by the structural plasticity of specific neural circuits such as the brain's dopamine (DA) system. Changes in dendritic morphology in the nucleus accumbens (NAc) accompany drug-induced enduring behavioral and molecular changes, yet ultrastructural changes in synapses following repeated exposure to drugs have not been well studied. The current study examines the role of DA D3 receptors in modulating locomotor activity induced by both acute and repeated methamphetamine (METH) administration and accompanying ultrastructural plasticity in the shell of NAc in mice. We found that D3 receptor mutant (D3−/−) mice exhibited attenuated acute locomotor responses as well as the development of behavioral sensitization to METH compared with wild-type mice. In the absence of obvious neurotoxic effects, METH induced similar increases in synaptic density in the shell of NAc in both wild-type and D3−/− mice. These results suggest that D3 receptors modulate locomotor responses to both acute and repeated METH treatment. In contrast, the D3 receptor is not obviously involved in modulating baseline or METH-induced ultrastructural changes in the NAc shell.
authors.affiliation: Department of Forensic Medicine, Xi'an Jiaotong University School of Medicine, Xi'an, Shannxi, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhu
authors.forename: Yanjiong
authors.initials: Y
authors.lastname: Chen
authors.forename: Na
authors.initials: N
authors.lastname: Zhao
authors.forename: Guofen
authors.initials: G
authors.lastname: Cao
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Dang
authors.forename: Wei
authors.initials: W
authors.lastname: Han
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.forename: Teng
authors.initials: T
authors.lastname: Chen
mesh_terms: D000818:Animals; D001369:Axons / Q000187:drug effects / Q000648:ultrastructure; D003712:Dendrites / Q000187:drug effects / Q000648:ultrastructure; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D004334:Drug Administration Schedule; D008297:Male; D008694:Methamphetamine / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D046529:Microscopy, Electron, Transmission; D009043:Motor Activity / Q000187:drug effects* / Q000235:genetics; D009474:Neurons / Q000187:drug effects / Q000648:ultrastructure*; D009714:Nucleus Accumbens / Q000166:cytology / Q000187:drug effects*; D050637:Receptors, Dopamine D3 / Q000172:deficiency / Q000378:metabolism*; D016622:Silver Staining; D013569:Synapses / Q000187:drug effects / Q000235:genetics / Q000648:ultrastructure; D013997:Time Factors
chemical_list: D018765:Dopamine Uptake Inhibitors; D050637:Receptors, Dopamine D3; D008694:Methamphetamine