title: Behavioral and neurophysiological effects of Ro 10-5824, a dopamine D4 receptor partial agonist, in common marmosets.
abstract: BACKGROUND
  Growing evidence suggests that dopamine D4 receptors (D4Rs) are involved in controlling executive functions. We have previously demonstrated that Ro 10-5824, a D4R partial agonist, improves the performance of common marmosets in the object retrieval detour (ORD) task. However, the neural mechanisms underlying this improvement are unknown.
  
  
  OBJECTIVE
  We investigated the behavioral and neurophysiological effects of Ro 10-5824 in common marmosets.
  
  
  METHODS
  The effects of Ro 10-5824 on cognitive function were evaluated using the ORD task. The neurophysiological effects of Ro 10-5824 were investigated by quantitative electroencephalography, especially on baseline gamma band activity in the frontal cortex. The effects of Ro 10-5824 on spontaneous locomotion were also assessed.
  
  
  RESULTS
  Systemic administration of Ro 10-5824 at 3 mg/kg significantly increased the success rate in the ORD task. At doses of 1 and 3 mg/kg, Ro 10-5824 increased baseline gamma band activity in the frontal cortex. Ro 10-5824 had no effect on spontaneous locomotion.
  
  
  CONCLUSIONS
  Activation of D4R by Ro 10-5824 improves the success rate in the ORD task and increases baseline gamma band activity in the frontal cortex without affecting locomotion in common marmosets. These findings highlight the role of D4R in gamma oscillations of non-human primates. As gamma oscillations are thought to be involved in attention and behavioral inhibition, our results suggest D4R agonists may improve these cognitive functions by modulating baseline gamma band activity in the frontal cortex.
authors.affiliation: Drug Development Research Laboratories, Sumitomo Dainippon Pharma Co. Ltd, 33-94 Enoki-cho, Suita, Osaka, 564-0053, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Nakazawa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Murai
authors.forename: Masanori
authors.initials: M
authors.lastname: Miyauchi
authors.forename: Manato
authors.initials: M
authors.lastname: Kotani
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Ikeda
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002144:Callithrix; D003071:Cognition / Q000187:drug effects; D018491:Dopamine Agonists / Q000494:pharmacology*; D004569:Electroencephalography / Q000187:drug effects; D056344:Executive Function / Q000187:drug effects; D005260:Female; D065818:Gamma Rhythm / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D017397:Prefrontal Cortex / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology*; D011743:Pyrimidines / Q000494:pharmacology*; D050638:Receptors, Dopamine D4 / Q000819:agonists*
chemical_list: D018491:Dopamine Agonists; D011725:Pyridines; D011743:Pyrimidines; C475158:RO 10-5824; D050638:Receptors, Dopamine D4