Degree Name

MA (Master of Arts)

Program

Psychology

Date of Award

12-2013

Committee Chair or Co-Chairs

Dr. Russ Brown

Committee Members

Dr. Eric Sellers, Dr. Matthew Palmateir

Abstract

This investigation was an analysis of the effects of methylphenidate (MPH; trade name: Ritalin) on drug reward using the conditioned place preference (CPP) behavioral paradigm in a rodent model and underlying mechanisms of this effect. Animals were conditioned in adolescence from postnatal day (P)33-39) or P44-49 with saline, 1 or 5 mg/kg MPH. Rats administered 5 mg/kg but not 1 mg/kg MPH, resulted in a significant preference that was more robust in younger male adolescent rats. The 5 mg/kg dose of MPH also resulted in a significant decrease of the dopamine transporter in both the nucleus accumbens and striatum, revealing dopamine clearance is decreased by MPH in brain areas that mediate reward. Finally, MPH-induced CPP was blocked by the dopamine D1 but not D2 antagonist, demonstrating the importance of the D1 receptor in the rewarding effects of MPH. These results demonstrate that dopamine mediates the rewarding effects of MPH in adolescence.

Document Type

Thesis - unrestricted

Copyright

Copyright by the authors.

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