Reduction of cocaine self-administration and D3 receptor-mediated behavior by two novel dopamine D3 receptor-selective partial agonists, OS-3-106 and WW-III-55

J Pharmacol Exp Ther. 2013 Nov;347(2):410-23. doi: 10.1124/jpet.112.202911. Epub 2013 Sep 9.

Abstract

Dopamine D3 receptor (D3R)-selective compounds may be useful medications for cocaine dependence. In this study, we identified two novel arylamide phenylpiperazines, OS-3-106 and WW-III-55, as partial agonists at the D3R in the adenylyl cyclase inhibition assay. OS-3-106 and WW-III-55 have 115- and 862-fold D3R:D2 receptor (D2R) binding selectivity, respectively. We investigated their effects (0, 3, 5.6, or 10 mg/kg) on operant responding by using a multiple variable-interval (VI) 60-second schedule that alternated components with sucrose reinforcement and components with intravenous cocaine reinforcement (0.375 mg/kg). Additionally, we evaluated the effect of OS-3-106 (10 mg/kg) on the dose-response function of cocaine self-administration and the effect of WW-III-55 (0-5.6 mg/kg) on a progressive ratio schedule with either cocaine or sucrose reinforcement. Both compounds were also examined for effects on locomotion and yawning induced by a D3R agonist. OS-3-106 decreased cocaine and sucrose reinforcement rates, increased latency to first response for cocaine but not sucrose, and downshifted the cocaine self-administration dose-response function. WW-III-55 did not affect cocaine self-administration on the multiple-variable interval schedule, but it reduced cocaine and sucrose intake on the progressive ratio schedule. Both compounds reduced locomotion at doses that reduced responding, and both compounds attenuated yawning induced by low doses of 7-OH-DPAT (a D3R-mediated behavior), but neither affected yawning on the descending limb of the 7-OH-DPAT dose-response function (a D2R-mediated behavior). Therefore, both compounds blocked a D3R-mediated behavior. However, OS-3-106 was more effective in reducing cocaine self-administration. These findings support D3Rs, and possibly D2Rs, as targets for medications aimed at reducing the motivation to seek cocaine.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzamides / administration & dosage
  • Benzamides / chemistry
  • Benzamides / therapeutic use*
  • Cocaine / administration & dosage*
  • Cocaine / adverse effects
  • Cocaine-Related Disorders / drug therapy*
  • Cocaine-Related Disorders / metabolism
  • Cocaine-Related Disorders / psychology
  • Dopamine Agonists / administration & dosage
  • Dopamine Agonists / chemistry
  • Dopamine Agonists / therapeutic use*
  • Drug Partial Agonism
  • Drug-Seeking Behavior / drug effects*
  • HEK293 Cells
  • Humans
  • Male
  • Molecular Structure
  • Piperazines / administration & dosage
  • Piperazines / chemistry
  • Piperazines / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Dopamine D3 / agonists*
  • Reinforcement, Psychology
  • Self Administration

Substances

  • Benzamides
  • Dopamine Agonists
  • OS-3-106
  • Piperazines
  • Receptors, Dopamine D3
  • WW-III-55
  • Cocaine