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Published on: November 11, 2013
Wheel running decreases the positive reinforcing effects of heroin
Mark A Smith1, Elizabeth G Pitts
1Department of Psychology, Davidson College, Davidson, NC 28035, USA. masmith@davidson.edu
Background:
The purpose of this study was to examine the effects of voluntary wheel running on the positive reinforcing effects of heroin in rats with an established history of drug self-administration.
Methods:
Rats were assigned to sedentary (no wheel) and exercise (wheel) conditions and trained to self-administer cocaine under positive reinforcement contingencies. Rats acquiring cocaine self-administration were then tested with various doses of heroin during daily test sessions.
Results:
Sedentary rats self-administered more heroin than exercising rats, and this effect was greatest at low and moderate doses of heroin.
Conclusion:
These data suggest that voluntary wheel running decreases the positive reinforcing effects of heroin.
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