title: Altered neuronal activity in the primary motor cortex and globus pallidus after dopamine depletion in rats.
abstract: The involvement of dopamine (DA) neuron loss in the etiology of Parkinson's disease has been well documented. The neural mechanisms underlying the effects of DA loss and the resultant motor dysfunction remain unknown. To gain insights into how loss of DA disrupts the electrical processes in the cortico-subcortical network, the present study explores the effects of DA neuron depletion on electrical activity in the primary motor cortex (M1), on the external and the internal segment of the globus pallidus (GPe and GPi respectively), and on their temporal relationships. Comparison of local field potentials (LFPs) in these brain regions from unilateral hemispheric DA neuron depleted rats and neurologically intact rats revealed that the spectrum power of LFPs in 12-70Hz (for M1, and GPe) and in 25-40Hz (for GPi) was significantly greater in the DA depleted rats than that in the control group. These changes were associated with a shortening of latency in LFP activities between M1 and GPe, from several hundred milliseconds in the intact animals to close to zero in the DA depleted animals. LFP oscillations in M1 were significantly more synchronized with those in GPe in the DA depleted rats compared with those in the control rats. By contrast, the synchronization of oscillation in LFP activities between M1 and GPi did not differ between the DA depleted and intact rats. Not surprisingly, rats that had DA neuron depletion spent more time along the ladder compared with the control rats. These data suggest that enhanced oscillatory activity and increased synchronization of LFPs may contribute to movement impairment in the rat model of Parkinson's disease.
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China. Electronic address: wangmin78@yahoo.com.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Xiwen
authors.initials: X
authors.lastname: Geng
authors.affiliation: Center for Behavioral Neuroscience, Neuroscience Institute, Georgia State University, Atlanta, GA 30302, United States.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Song
authors.affiliation: Center for Behavioral Neuroscience, Neuroscience Institute, Georgia State University, Atlanta, GA 30302, United States.
authors.forename: H Elliott
authors.initials: HE
authors.lastname: Albers
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Maoquan
authors.initials: M
authors.lastname: Yang
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Jinlu
authors.initials: J
authors.lastname: Xie
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Qingyang
authors.initials: Q
authors.lastname: Qu
authors.affiliation: Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
authors.forename: Tingting
authors.initials: T
authors.lastname: He
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D004195:Disease Models, Animal; D059290:Dopaminergic Neurons / Q000473:pathology*; D055724:Electrophysiological Phenomena / Q000502:physiology*; D005917:Globus Pallidus / Q000503:physiopathology*; D008297:Male; D009044:Motor Cortex / Q000503:physiopathology*; D010300:Parkinson Disease / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar
keywords: Basal ganglia; Globus pallidus; Local field potential; Microelectrode; Motor cortex; Parkinson's disease