Diazepam in the ventral striatum dissociates dopamine-dependent and dopamine-independent place conditioning

Neuroreport. 2000 Aug 3;11(11):2553-7. doi: 10.1097/00001756-200008030-00041.

Abstract

We have previously shown that diazepam blocks both the formation and the expression of amphetamine-induced conditioned place preference (CPP), but has no effect on the CPP induced by morphine. Because diazepam reduces dopamine activity in the nucleus accumbens, three experiments were conducted in order to investigate whether diazepam selectively blocks the expression of place conditioning dependent on mesolimbic dopamine. The first experiment found that systemic diazepam blocked the expression of conditioned place aversion induced by the kappa-receptor agonist U50-488. The second and third experiments demonstrated that intra-cranial injections of diazepam in the nucleus accumbens blocked the expression of amphetamine CPP but not of morphine CPP. It is concluded that diazepam interferes with mesolimbic dopamine-dependent motivational effects of drugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer / pharmacology
  • Amphetamine / pharmacology
  • Animals
  • Conditioning, Psychological / drug effects*
  • Conditioning, Psychological / physiology
  • Diazepam / pharmacology*
  • Dopamine / metabolism*
  • Drug Interactions / physiology
  • Male
  • Morphine / pharmacology
  • Motor Activity / drug effects
  • Motor Activity / physiology
  • Neural Pathways / cytology
  • Neural Pathways / drug effects*
  • Neural Pathways / metabolism
  • Neurons / cytology
  • Neurons / drug effects*
  • Neurons / metabolism
  • Nucleus Accumbens / cytology
  • Nucleus Accumbens / drug effects*
  • Nucleus Accumbens / metabolism
  • Rats
  • Rats, Long-Evans
  • Receptors, Opioid, kappa / agonists
  • Receptors, Opioid, kappa / metabolism
  • Substance-Related Disorders / drug therapy
  • Substance-Related Disorders / metabolism
  • Substance-Related Disorders / physiopathology
  • Ventral Tegmental Area / cytology
  • Ventral Tegmental Area / drug effects*
  • Ventral Tegmental Area / metabolism

Substances

  • Receptors, Opioid, kappa
  • 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer
  • Morphine
  • Amphetamine
  • Diazepam
  • Dopamine