Dopamine depletion increases the power and coherence of high-voltage spindles in the globus pallidus and motor cortex of freely moving rats

• Published in: Brain research Vol. 1465; pp. 66 - 79
• Main Authors: Ge, Shunnan, Yang, Chen, Li, Min, Li, Jiang, Chang, Xiaozan, Fu, Jian, Chen, Lei, Chang, Chongwang, Wang, Xuelian, Zhu, Junling, Gao, Guodong
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 17.07.2012; Elsevier
• Subjects: 6-Hydroxydopamine; 6-OHDA; Adult and adolescent clinical studies; animal disease models; Animal models; Animals; Basal ganglia; Biological and medical sciences; brain; Circuits; cortex; Cortex (motor); Cortical Synchronization - physiology; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Dopamine; Dopamine - deficiency; Dopamine - physiology; Ganglia; Globus pallidus; Globus Pallidus - metabolism; Globus Pallidus - physiopathology; High-voltage spindle; Male; Medical sciences; Motor Activity - physiology; Motor Cortex - metabolism; Motor Cortex - physiopathology; Movement - physiology; Movement disorders; Neostriatum; Neural Pathways - physiology; Neurodegenerative diseases; Neurology; Organic mental disorders. Neuropsychology; Oscillations; Parkinson disease; Parkinson's disease; Parkinsonian Disorders - chemically induced; Parkinsonian Disorders - metabolism; Parkinsonian Disorders - physiopathology; patients; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Random Allocation; Rats; Rats, Sprague-Dawley; Spindles; Substantia nigra; Synchronization; electrocorticogram; basal ganglia; Parkinson's disease; BG; M2 cortex; substantia nigra pars reticulate; 6-OHDA; M1 cortex; STN; LFP; 3,3-diaminobenzidine tetrahydrochloride; globus pallidus; GPe; primary motor cortex; high-voltage spindles; DAB; GP; SNc; HVSs; local-field potential; Synchronization; MSNs; tyrosine hydroxylase; substantia nigra pars compacta; secondary motor cortex; 6-hydroxydopamine; external globus pallidus; PD; TH; ECoG; SNr; subthalamic nucleus; medium spiny neurons; High-voltage spindle; Basal ganglia; Motor pathway; Rat; Central nervous system; Parkinson disease; Oxidopamine; Pallidum; Encephalon; Motor cortex; Degenerative disease; Nervous system diseases; Dopamine; Rodentia; Basal ganglion; Catecholamine; Cerebral disorder; Vertebrata; Mammalia; Depletion; Animal; Central nervous system disease; Coherence; Neurotransmitter; Extrapyramidal syndrome
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/j.brainres.2012.05.002

Abstract Studies on patients with Parkinson's disease and in animal models have observed enhanced synchronization of oscillations in several frequency bands within and between the cortical–basal ganglia (BG) structures. Recent research has also shown that synchronization of high-voltage spindles (HVSs) in the cortex, striatum and substantia nigra pars reticulate is increased by dopamine depletion. However, more evidence is needed to determine whether HVS activity in the whole cortex–BG network represents homologous alteration following dopamine depletion. As the globus pallidus (GP) is in a central position to propagate and synchronize oscillations in the cortical–BG circuits, we employed local-field potentials and electrocorticogram to simultaneously record oscillations in the GP and primary (M1) and secondary (M2) motor cortices on freely moving 6-hydroxydopamine (6-OHDA) lesioned and control rats. Results showed that HVS episodes recorded from GP, and M2 and M1 cortex areas were more numerous and longer in 6-OHDA lesioned rats compared to controls. Relative power associated with HVS activity in the GP, and M2 and M1 cortices of 6-OHDA lesioned rats was significantly greater than that for control rats. Coherence values for HVS activity between the GP, and M2 and M1 cortex areas were significantly increased by dopamine depletion. Time lag between the M1 cortex HVS and GP HVS was significantly shorter for dopamine depleted than normal rats. Findings indicate a crucial rule for dopamine in the regulation of HVS activity in the whole cortical–BG circuit, and suggest a close relationship between abnormally synchronized HVS oscillations in the cortex–BG network and Parkinson's disease.