title: Lithium, but not valproic acid or carbamazepine, suppresses impulsive-like action in rats.
abstract: BACKGROUND
  Higher impulsivity is a pathological symptom in several psychiatric disorders, including bipolar disorder, and is a risk factor for suicide.
  
  
  OBJECTIVE
  Our goal was to determine whether major mood-stabilizing drugs used for the treatment of bipolar disorder could suppress impulsive-like action in the three-choice serial reaction time task (3-CSRTT).
  
  
  METHODS
  Following training for the 3-CSRTT, rats were acutely administered lithium chloride (LiCl; 0, 3.2, 10, and 32 mg/kg, i.p.), valproic acid (0, 10, 32, and 100 mg/kg, i.p.), or carbamazepine (0, 10, 20, and 30 mg/kg, i.p.). To assess the anorexic effects of lithium, a simple food consumption test was conducted.
  
  
  RESULTS
  LiCl dose-dependently decreased the number of premature responses, an index of impulsive-like action. A high dose of LiCl (32 mg/kg) decreased food consumption, but its anorexic effects were not correlated with the effects of LiCl on premature responses. A moderate dose of LiCl (20 mg/kg) significantly reduced the number of premature responses without affecting motivation-related measures in the 3-CSRTT or the amount of food consumption. Although carbamazepine prolonged reward latency, an index of motivation for food, neither valproic acid nor carbamazepine significantly affected premature responses.
  
  
  CONCLUSIONS
  It is likely that lithium has a suppressive effect on impulsive action independent of the anorexic effect. Lithium may suppress impulsive behavior and thereby decrease the risk of suicide. The present results could provide an explanation for the antisuicidal effects of lithium and suggest that lithium could be a beneficial treatment for impulsivity-related disorders.
authors.affiliation: Department of Neuropharmacology, Graduate School of Medicine, Hokkaido University, N15 W7 Kita-ku, Sapporo 060-8638, Japan. gwd0701@yahoo.co.jp
authors.forename: Yu
authors.initials: Y
authors.lastname: Ohmura
authors.forename: Iku
authors.initials: I
authors.lastname: Tsutsui-Kimura
authors.forename: Haruko
authors.initials: H
authors.lastname: Kumamoto
authors.forename: Masabumi
authors.initials: M
authors.lastname: Minami
authors.forename: Takeshi
authors.initials: T
authors.lastname: Izumi
authors.forename: Taku
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yoshida
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Yoshioka
mesh_terms: D000818:Animals; D002220:Carbamazepine / Q000494:pharmacology / Q000627:therapeutic use*; D002755:Choice Behavior / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects; D007175:Impulsive Behavior / Q000188:drug therapy*; D018021:Lithium Chloride / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D012691:Serial Learning / Q000187:drug effects; D014635:Valproic Acid / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D002220:Carbamazepine; D014635:Valproic Acid; D018021:Lithium Chloride