Motor learning in animal models of Parkinson's disease: Aberrant synaptic plasticity in the motor cortex.
In Parkinson's disease (PD), dopamine depletion causes major changes in the brain, resulting in the typical cardinal motor features of the disease. PD neuropathology has been restricted to postmortem examinations, which are limited to only a single time of PD progression. Models of PD in which dopamine tone in the brain is chemically or physically disrupted are valuable tools in understanding the mechanisms of the disease. The basal ganglia have been well studied in the context of PD, and circuit changes in response to dopamine loss have been linked to the motor dysfunctions in PD. However, the etiology of the cognitive dysfunctions that are comorbid in PD patients has remained unclear until now. In this article, we review recent studies exploring how dopamine depletion affects the motor cortex at the synaptic level. In particular, we highlight our recent findings on abnormal spine dynamics in the motor cortex of PD mouse models through in vivo time-lapse imaging and motor skill behavior assays. In combination with previous studies, a role of the motor cortex in skill learning and the impairment of this ability with the loss of dopamine are becoming more apparent. Taken together, we conclude with a discussion on the potential role for the motor cortex in PD, with the possibility of targeting the motor cortex for future PD therapeutics. © 2017 International Parkinson and Movement Disorder Society.
Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China.|Ministry of Education (MoE) Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan, China.
Tonghui
T
Xu
Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan, China.|Ministry of Education (MoE) Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan, China.
Shaofang
S
Wang
Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, California, USA.|Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, California, USA.
Rupa R
RR
Lalchandani
Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, California, USA.|Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, California, USA.
Jun B
0000-0003-0690-1312
JB
Ding
D000818:Animals; D004195:Disease Models, Animal; D015259:Dopamine Agents / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007858:Learning / Q000502:physiology*; D009044:Motor Cortex / Q000187:drug effects / Q000473:pathology*; D019957:Motor Skills Disorders / Q000209:etiology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D010300:Parkinson Disease / Q000150:complications / Q000188:drug therapy / Q000473:pathology*
D015259:Dopamine Agents
Dopamine; Motor cortex; Parkinson's disease; Skill learning; Spine dynamics; Synaptic plasticity