title: Access to a running wheel decreases cocaine-primed and cue-induced reinstatement in male and female rats.
abstract: BACKGROUND
  Relapse to drug use after a period of abstinence is a persistent problem in the treatment of cocaine dependence. Physical activity decreases cocaine self-administration in laboratory animals and is associated with a positive prognosis in human substance-abusing populations. The purpose of this study was to examine the effects of long-term access to a running wheel on drug-primed and cue-induced reinstatement of cocaine-seeking behavior in male and female rats. methods: Long-Evans rats were obtained at weaning and assigned to sedentary (no wheel) and exercising (access to wheel) groups for the duration of the study. After 6 weeks, rats were implanted with intravenous catheters and trained to self-administer cocaine for 14 days. After training, saline was substituted for cocaine and responding was allowed to extinguish, after which cocaine-primed reinstatement was examined in both groups. Following this test, cocaine self-administration was re-established in both groups for a 5-day period. Next, a second period of abstinence occurred in which both cocaine and the cocaine-associated cues were withheld. After 5 days of abstinence, cue-induced reinstatement was examined in both groups.
  
  
  RESULTS
  Sedentary and exercising rats exhibited similar levels of cocaine self-administration, but exercising rats responded less than sedentary rats during extinction. In tests of cocaine-primed and cue-induced reinstatement, exercising rats responded less than sedentary rats, and this effect was apparent in both males and females.
  
  
  CONCLUSIONS
  These data indicate that long-term access to a running wheel decreases drug-primed and cue-induced reinstatement, and that physical activity may be effective at preventing relapse in substance-abusing populations.
authors: Department of Psychology, Davidson College, Davidson, NC 28035, USA. masmith@davidson.edu
authors: Mark A
authors: MA
authors: Smith
authors: Michael M
authors: MM
authors: Pennock
authors: Katherine L
authors: KL
authors: Walker
authors: Kimberly C
authors: KC
authors: Lang
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003042:Cocaine / Q000008:administration & dosage*; D003463:Cues; D005108:Extinction, Psychological / Q000187:drug effects*; D005260:Female; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D012054:Reinforcement, Psychology; D012646:Self Administration
chemical_list: D003042:Cocaine