title: Remote effects on the striatal dopamine system after fluid percussion injury.
abstract: OBJECTIVE
  To investigate the effects of traumatic brain injury (TBI) on the dopamine system in the brain at different distances from the impaction site, we compared the release, reuptake, metabolism, and release probability of dopamine on the sides of the brain ipsilateral and contralateral to the injury at different time points after varying severities of fluid percussion injuries.
  
  
  METHODS
  Tonic (1-pulse evoked) and bursting (10-pulse evoked) dopamine release changes in the ipsilateral and contralateral sides of the striatum resulting from mild (2-Pa) and severe (6-Pa) levels of fluid percussion injury were analyzed at the acute (2h and 24h), subacute (1 and 2 weeks), and chronic stages (4, 6, and 8 weeks) after injury by using fast scan cyclic voltammetry to measure brain slices. The metabolic rate of striatal dopamine was surveyed using high-performance liquid chromatography. The microglia reaction was analyzed using immunohistochemistry at each stage.
  
  
  RESULTS
  In 6-Pa injured animals, for both tonic and bursting dopamine release, reuptake and release probability were suppressed on both the ipsilateral and contralateral sides of the striatum from the acute to the chronic stage. These neuronal activities were also affected at the subacute stage on both sides of the striatum in 2-Pa injured animals. The turnover rate of dopamine was not affected in the 2-Pa injured animals but increased gradually during the chronic stage in the 6-Pa injured group.
  
  
  CONCLUSIONS
  TBI suppresses dopamine release and reuptake and affects the metabolic rate and release probability of dopamine on the sides of the nigrostriatal system both ipsilateral and contralateral to the injury during both the acute and subacute stages after the injury.
authors.affiliation: Department of Pharmacology, National Defense Medical Center, No. 161, Sec. 6, Minquan E. Rd., Neihu Dist., Taipei City 114, Taiwan, ROC.
authors.forename: Eagle Yi-Kung
authors.initials: EY
authors.lastname: Huang
authors.affiliation: Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, 4F, No. 325, 2nd Sec., Cheng-Kung Road, Neihu District, Taipei City 114, Taiwan, ROC.
authors.forename: Tung-Han
authors.initials: TH
authors.lastname: Tsai
authors.affiliation: Graduate Institute of Computer and Communication Engineering, National Taipei University of Technology, Taipei, No. 1, 3rd Sec., Zhongxiao E. Rd., Taipei City 106, Taiwan, ROC.
authors.forename: Tung-Tai
authors.initials: TT
authors.lastname: Kuo
authors.affiliation: Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, 4F, No. 325, 2nd Sec., Cheng-Kung Road, Neihu District, Taipei City 114, Taiwan, ROC.
authors.forename: Jing-Jr
authors.initials: JJ
authors.lastname: Tsai
authors.affiliation: Department of Pharmacology, National Defense Medical Center, No. 161, Sec. 6, Minquan E. Rd., Neihu Dist., Taipei City 114, Taiwan, ROC.
authors.forename: Pi-Fen
authors.initials: PF
authors.lastname: Tsui
authors.affiliation: School of Public Health, National Defense Medical Center, No. 161, Sec. 6, Minquan E. Rd., Neihu Dist., Taipei City 114, Taiwan, ROC.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Chou
authors.affiliation: Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, 4F, No. 325, 2nd Sec., Cheng-Kung Road, Neihu District, Taipei City 114, Taiwan, ROC.
authors.forename: Hsin-I
authors.initials: HI
authors.lastname: Ma
authors.affiliation: Department of Neurosurgery, Taipei Medical University Hospital, the Ph.D. Program for Neural Regenerative Medicine, Graduate Institute of Neural Regenerative Medicine, Taipei Medical University, Taipei, No. 252, Wu-Hsing Street, Taipei City 110, Taiwan, ROC.
authors.forename: Yung-Hsiao
authors.initials: YH
authors.lastname: Chiang
authors.affiliation: Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, 4F, No. 325, 2nd Sec., Cheng-Kung Road, Neihu District, Taipei City 114, Taiwan, ROC. Electronic address: chenyh178@gmail.com.
authors.forename: Yuan-Hao
authors.initials: YH
authors.lastname: Chen
mesh_terms: D000208:Acute Disease; D000818:Animals; D001930:Brain Injuries / Q000503:physiopathology*; D002452:Cell Count; D002851:Chromatography, High Pressure Liquid; D002908:Chronic Disease; D003342:Corpus Striatum / Q000503:physiopathology*; D004298:Dopamine / Q000378:metabolism*; D004558:Electric Stimulation; D007839:Functional Laterality; D007150:Immunohistochemistry; D008297:Male; D008839:Microelectrodes; D017628:Microglia / Q000502:physiology*; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function / Q000502:physiology; D012720:Severity of Illness Index; D013997:Time Factors; D046509:Tissue Culture Techniques
chemical_list: D004298:Dopamine
keywords: Dopamine releasing and reuptake; Fast-Scan Cyclic Voltammetry (FSCV); Fluid percussion injury; High-pressure liquid chromatography (HPLC); Neuroinflammation