title: Acute bouts of wheel running decrease cocaine self-administration: Influence of exercise output.
abstract: Exercise is associated with lower rates of drug use in human populations and decreases drug self-administration in laboratory animals. Most of the existing literature examining the link between exercise and drug use has focused on chronic, long-term exercise, and very few studies have examined the link between exercise output (i.e., amount of exercise) and drug self-administration. The purpose of this study was to examine the effects of acute bouts of exercise on cocaine self-administration, and to determine whether these effects were dependent on exercise output and the time interval between exercise and drug self-administration. Female rats were trained to run in automated running wheels, implanted with intravenous catheters, and allowed to self-administer cocaine on a fixed ratio (FR1) schedule of reinforcement. Immediately prior to each test session, subjects engaged in acute bouts of exercise in which they ran for 0, 30, or 60min at 12m/min. Acute bouts of exercise before test sessions decreased cocaine self-administration in an output-dependent manner, with the greatest reduction in cocaine intake observed in the 60-min exercise condition. Exercise did not reduce cocaine self-administration when wheel running and test sessions were separated by 12h, and exercise did not reduce responding maintained by food or responding during a saline substitution test. These data indicate that acute bouts of exercise decrease cocaine self-administration in a time- and output-dependent manner. These results also add to a growing body of literature suggesting that physical activity may be an effective component of drug abuse treatment programs.
authors.affiliation: Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC 28035, USA. Electronic address: masmith@davidson.edu.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Smith
authors.affiliation: Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC 28035, USA.
authors.forename: Gaylen E
authors.initials: GE
authors.lastname: Fronk
authors.affiliation: Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC 28035, USA.
authors.forename: Huailin
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC 28035, USA.
authors.forename: Charlotte P
authors.initials: CP
authors.lastname: Magee
authors.affiliation: Department of Psychology, Program in Neuroscience, Davidson College, Davidson, NC 28035, USA.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Robinson
mesh_terms: D000818:Animals; D003042:Cocaine / Q000008:administration & dosage*; D005260:Female; D009043:Motor Activity; D010805:Physical Conditioning, Animal; D051381:Rats; D020318:Rats, Long-Evans; D012055:Reinforcement Schedule; D012646:Self Administration
chemical_list: D003042:Cocaine
keywords: Cocaine; Exercise; Rat; Self-administration; Wheel