Discriminative Stimulus Effects of (+)-7-OH-DPAT in Rats: Importance of D₃ Receptors

Author

April J. Christian

Date of Award

12-1999

Degree Name

Master of Arts

Department

Psychology

First Advisor

Dr. Lisa Baker

Second Advisor

Dr. Scott Kollins

Third Advisor

Dr. Alan Poling

Access Setting

Masters Thesis-Open Access

Abstract

Despite the reported relatively high binding affinity of 7-OH-DPAT to dopamine D₃ receptors, results of recent investigations with the highly selective 03 receptor antagonist, PNU-99194A have questioned the importance of 03 receptors in the discriminative stimulus effects of 7-OH-DPAT. In the present study, sixteen male Sprague- Dawley rats (N=8/group) were trained to discriminate (+)- 7-OH-DPAT (0.03 mg/kg, sc) from saline in a two-lever operant procedure using a fixed-ratio 20 schedule of water reinforcement. After stable performance was established, substitution tests were conducted with the D₃-prefering agonist, (+)-PD-128907 and the psychostimulant cocaine. Additionally, antagonism were conducted with the selective D₂ antagonist, remoxipride. Cocaine failed to produce generalization, but (+)-PD-128907 did substitute for the (+)-7-OH-DPAT cue. Remoxipride appeared to partially block (+)-7-OH-DAPT discrimination. Future investigations with highly selective D₃ antagonists are discussed.

Recommended Citation

Christian, April J., "Discriminative Stimulus Effects of (+)-7-OH-DPAT in Rats: Importance of D₃ Receptors" (1999). Masters Theses. 4622.
https://scholarworks.wmich.edu/masters_theses/4622