title: The subthalamic activity and striatal monoamine are modulated by subthalamic stimulation.
abstract: OBJECTIVE
  Not all the mechanisms by which subthalamic nucleus deep brain stimulation (STN-DBS) alleviates parkinsonian symptoms have been clarified as yet. The levels of striatal monoamine and the subthalamic beta activity might contribute to its efficacy. However, their direct relationship is unclear. We aimed to examine the correlation between the striatal monoamine and the STN beta activity induced by STN-DBS.
  
  
  METHODS
  Experiments were performed under urethane anesthesia in normal (n=4) and 6-hydroxydopamine hemi-lesioned Parkinson's disease (PD) model rats (n=5). STN-DBS was applied to the left STN, and local field potential (LFP) was recorded before and after STN-DBS. Striatal extracellular fluid was collected before, during, and after STN-DBS. Spectral analysis of STN-LFP was performed, and the levels of monoamine were measured.
  
  
  RESULTS
  The levels of 3-4-dihydroxyphenylacetic acid (DOPAC) were significantly decreased after the cessation of stimulation in PD model rats. The levels of none of the monoamines were significantly affected in normal rats. The STN beta power was significantly elevated after the cessation of stimulation in normal rats but was significantly decreased in PD model rats. The STN beta power and the levels of DOPAC and 5-HT was positively correlated in PD model rats, whereas the levels of dopamine and 5-HT showed positive correlation and the levels of DOPAC and Homovanillic acid (HVA) showed negative correlation in normal rats.
  
  
  CONCLUSIONS
  STN-DBS could decrease the levels of DOPAC and the STN beta power in a PD model rat. The STN beta power and the levels of striatal monoamine might be differentially correlated between normal and PD model rats.
authors.affiliation: Department of Neurology, Chiba University Graduate School of Medicine, Chiba, Japan. Electronic address: tatsuya-yamamoto@mbc.nifty.com.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Neurology, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Uchiyama
authors.affiliation: Neurology Division, Department of Internal Medicine, Sakura Medical Center, Toho University, Sakura, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Sakakibara
authors.affiliation: Department of Neurology, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Taniguchi
authors.affiliation: Department of Neurology, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kuwabara
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003342:Corpus Striatum / Q000378:metabolism*; D004195:Disease Models, Animal; D004298:Dopamine / Q000378:metabolism; D004558:Electric Stimulation / Q000379:methods*; D005260:Female; D006719:Homovanillic Acid / Q000378:metabolism; D009043:Motor Activity / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D016627:Oxidopamine / Q000633:toxicity; D010300:Parkinson Disease / Q000209:etiology / Q000473:pathology / Q000628:therapy*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013057:Spectrum Analysis; D020531:Subthalamic Nucleus / Q000166:cytology / Q000502:physiology*
chemical_list: D015306:Biogenic Monoamines; D015102:3,4-Dihydroxyphenylacetic Acid; D016627:Oxidopamine; D004298:Dopamine; D006719:Homovanillic Acid
keywords: 3–4-dihydroxyphenylacetic acid; 5-HIAA; 5-hydroxyindoleacetic acid; 6-OHDA; 6-hydroxydopamine; DA; DOPAC; EDTA; FFT; H(2)O(2); HPLC; HVA; Homovanillic acid; LFP; PBS; PBS containing 0.05% Tween-20; PBST; PD; PSD; Parkinson’s disease; SNc; STN-DBS; Substantia nigra pars compacta; deep brain stimulation; dopamine; ethylenediaminetetraacetic acid; fast Fourier transform; high-performance liquid chromatography; hydrogen peroxide; local field potential; phosphate-buffered saline; power spectral density; striatal monoamine; subthalamic nucleus; subthalamic nucleus deep brain stimulation