title: Effects of dopamine D2 agonist quinpirole on neuronal activity of anterior cingulate cortex and striatum in rats.
abstract: BACKGROUND
  The influence of acute D2 agonist quinpirole on locomotor activity has been effectively characterized. However, few studies have addressed the dynamic changes in neuronal activity of the anterior cingulate cortex (ACC) and striatum (STR), two crucial regions for cognitive and motor functions, after quinpirole administration.
  
  
  OBJECTIVE
  This study was conducted in order to acquire detailed information on the evoked activity of the neurons in the ACC and STR after acute quinpirole administration.
  
  
  METHODS
  Multichannel electrophysiological recording was used for tracking neuronal activity in the ACC and STR of urethane-anesthetized rats after administration of saline or 0.05 or 0.5 mg/kg quinpirole.
  
  
  RESULTS
  In contrast to the responses to saline, quinpirole dose-dependently increased the ratio of neurons, the activity of which was inhibited in the ACC and STR. By examining the ensemble neuronal activities of inhibition-responded neurons, there was no significant activity difference among the "treatments" (saline and low- and high-dose quinpirole), the "periods" (the duration of 0-15 and 16-45 min after i.v. injection), and the interaction between "treatments" and "periods." Regarding activation-responded neurons, however, there was a significant "periods" difference in both ACC and STR, and the activity of 16-45 min was significantly higher than the activity of 0-15 min after high-dose quinpirole administration in ACC (p < 0.05) and STR (p < 0.001).
  
  
  CONCLUSIONS
  Dose-dependent ACC and STR neuronal responses to quinpirole may offer a possible mechanism for understanding the locomotor responses to quinpirole in behaving rats. The late excitatory effect of high-dose quinpirole in the STR further suggests that this region would be critical for the activation of locomotor activity.
authors: Institute of Electronics Engineering, National Taiwan University, Taipei, Taiwan.
authors: Jian-Jia
authors: JJ
authors: Huang
authors: Chen-Tung
authors: CT
authors: Yen
authors: Tzu-Lan
authors: TL
authors: Liu
authors: Hen-Wai
authors: HW
authors: Tsao
authors: Ju-Wei
authors: JW
authors: Hsu
authors: Meng-Li
authors: ML
authors: Tsai
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000502:physiology; D018491:Dopamine Agonists / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D006179:Gyrus Cinguli / Q000187:drug effects* / Q000502:physiology; D053444:Inhibitory Postsynaptic Potentials / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D019257:Quinpirole / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D017448:Receptors, Dopamine D2 / Q000819:agonists*; D013997:Time Factors
chemical_list: D018491:Dopamine Agonists; D017448:Receptors, Dopamine D2; D019257:Quinpirole