Environmental context modulates the ability of cocaine and amphetamine to induce c-fos mRNA expression in the neocortex, caudate nucleus, and nucleus accumbens

Brain Res. 2001 Nov 30;920(1-2):106-16. doi: 10.1016/s0006-8993(01)03040-2.

Abstract

We reported previously that environmental novelty enhances the acute psychomotor activating effects of amphetamine, its ability to induce behavioral sensitization, and its ability to induce c-fos mRNA in the striatum and other structures, relative to when amphetamine is given in the home cage. The purpose of the present experiment was 2-fold: to determine (1) whether environmental novelty has a similar effect on the ability of cocaine to induce c-fos mRNA, and (2) whether this effect is seen in neurologically-intact rats (in previous experiments we studied the intact hemisphere of rats with a unilateral 6-OHDA lesion). In the dorsal portion of the caudate putamen, core and shell of the nucleus accumbens, and in several cortical regions, both amphetamine (1.5 mg/kg) and cocaine (15 mg/kg) induced higher levels of c-fos mRNA expression when administered in a novel environment, relative to when they were administered in the home cage. The ability of environmental context to modulate psychostimulant drug-induced immediate early gene expression may be related to its ability to modulate forms of drug experience-dependent plasticity, such as behavioral sensitization.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amphetamine / pharmacology*
  • Animals
  • Caudate Nucleus / drug effects
  • Caudate Nucleus / metabolism*
  • Cocaine / pharmacology*
  • Dopamine Uptake Inhibitors / pharmacology*
  • Environment*
  • In Situ Hybridization
  • Male
  • Motor Activity / drug effects
  • Neocortex / drug effects
  • Neocortex / metabolism*
  • Nucleus Accumbens / drug effects
  • Nucleus Accumbens / metabolism*
  • Parietal Lobe / drug effects
  • Parietal Lobe / metabolism
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / metabolism
  • Proto-Oncogene Proteins c-fos / biosynthesis*
  • RNA, Messenger / biosynthesis*
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Dopamine Uptake Inhibitors
  • Proto-Oncogene Proteins c-fos
  • RNA, Messenger
  • Amphetamine
  • Cocaine