The dopamine uptake inhibitor 3 alpha-[bis(4'-fluorophenyl)metoxy]-tropane reduces cocaine-induced early-gene expression, locomotor activity, and conditioned reward

Neuropsychopharmacology. 2009 Nov;34(12):2497-507. doi: 10.1038/npp.2009.78. Epub 2009 Jul 15.

Abstract

Benztropine (BZT) analogs, a family of high-affinity dopamine transporter ligands, are molecules that exhibit pharmacological and behavioral characteristics predictive of significant therapeutic potential in cocaine addiction. Here, we examined in mice the effects of 3 alpha-[bis(4'-fluorophenyl)metoxy]-tropane (AHN-1055) on motor activity, conditioned place preference (CPP) and c-Fos expression in the striatum. AHN-1055 produced mild attenuation of spontaneous locomotor activity at a low dose (1 mg/kg) and weak stimulation at a higher dose (10 mg/kg). In parallel, the BZT analog significantly increased c-Fos expression in the dorsolateral caudoputamen at the high dose, whereas producing marginal decreases at low and moderate doses (1, 3 mg/kg) in both dorsal and ventral striatum. Interaction assays showed that cocaine's ability to stimulate locomotor activity was decreased by AHN-1055 treatment, but not by treatment with D-amphetamine. Such reduced ability did not result from an increase in stereotyped behavior. Another dopamine uptake inhibitor, nomifensine, decreased cocaine-induced locomotor activity but evoked by itself intense motor stereotypies. Remarkably, the BZT analog dose-dependently blocked cocaine-induced CPP without producing CPP when given alone, and blocked in conditioned mice cocaine-stimulated early-gene activation in the nucleus accumbens and dorsomedial striatum. These observations provide evidence that AHN-1055 does not behave as a classical psychomotor stimulant and that some of its properties, including attenuation of cocaine-induced striatal c-Fos expression, locomotor stimulation, and CPP, support its candidacy, and that of structurally related molecules, as possible pharmacotherapies in cocaine addiction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benztropine / administration & dosage
  • Benztropine / analogs & derivatives*
  • Benztropine / pharmacology
  • Brain / drug effects
  • Brain / metabolism
  • Cocaine / pharmacology
  • Cocaine-Related Disorders / drug therapy*
  • Conditioning, Classical / drug effects*
  • Dopamine Uptake Inhibitors / administration & dosage
  • Dopamine Uptake Inhibitors / pharmacology*
  • Dose-Response Relationship, Drug
  • Gene Expression / drug effects*
  • Male
  • Mice
  • Motor Activity / drug effects*
  • Nomifensine / pharmacology
  • Proto-Oncogene Proteins c-fos / metabolism
  • Reward
  • Space Perception / drug effects
  • Stereotyped Behavior / drug effects

Substances

  • Dopamine Uptake Inhibitors
  • N-methyl-3-(bis(4'-fluorophenyl)methoxy)tropane
  • Proto-Oncogene Proteins c-fos
  • Nomifensine
  • Benztropine
  • Cocaine