Psychopharmacology

, Volume 84, Issue 2, pp 167–173

Destruction of dopamine in the nucleus accumbens selectively attenuates cocaine but not heroin self-administration in rats

  • Hugh O. Pettit
  • Aaron Ettenberg
  • Floyd E. Bloom
  • George F. Koob
Original Investigations

DOI: 10.1007/BF00427441

Cite this article as:
Pettit, H.O., Ettenberg, A., Bloom, F.E. et al. Psychopharmacology (1984) 84: 167. doi:10.1007/BF00427441

Abstract

The hypothesis that separate neural systems mediate the reinforcing properties of opioid and psychomotor stimulant drugs was tested by examining the role of mesolimbic dopamine (DA) neurons in maintaining intravenous heroin and cocaine self-administration. After local destruction of the DA terminals in the nucleus accumbens (NAcc) with 6-hydroxydopamine (6-OHDA), rats trained to self-administer cocaine and heroin on alternate days were observed for changes in their drug-seeking behaviors. Postlesion responding for cocaine showed a time-dependent decrease or extinction, whereas heroin self-administration showed a time-dependent recovery. By the fifth trial postlesion, heroin self-administration had recovered to 76% of prelesion baseline levels, but cocaine self-administration had dropped to 30% of prelesion baseline rates. Thus, selective lesions of the DA terminals in the nucleus accumbens significantly attenuate cocaine but not heroin self-administration. These data support the hypothesis that independent neural subtrates are responsible for the reinforcing actions of these two drugs.

Key words

CocaineHeroinSelf-administrationOpiatePsychomotor stimulantDopamineNucleus accumbens6-HydroxydopamineReinforcement

Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • Hugh O. Pettit
    • 1
  • Aaron Ettenberg
    • 2
  • Floyd E. Bloom
    • 3
  • George F. Koob
    • 3
  1. 1.Department of PsychologyTexas Christian UniversityFort WorthUSA
  2. 2.Department of PsychologyUniversity of CaliforniaSanta BarbaraUSA
  3. 3.Division of Preclinical Neuroscience and EndocrinologyScripps Clinic and Research Fdn.La JollaUSA