Fos regulates neuronal activity in the nucleus accumbens

Neurosci Lett. 2008 Dec 19;448(1):157-60. doi: 10.1016/j.neulet.2008.10.025. Epub 2008 Oct 14.


Repeated exposure to drugs of abuse induces a variety of persistent changes in the brain and the dopamine D1 receptor plays a major role in the process. To understand intracellular mechanisms contributing to cocaine-induced neuroadaptations, we previously examined the role of the immediate early gene Fos using a mouse in which Fos is disrupted primarily in D1 receptor-expressing neurons in the brain. We found that both dendritic remodeling of medium spiny neurons and behavioral sensitization induced by repeated exposure to cocaine are attenuated in the mutant mice. Moreover, the expression of genes encoding several transcription factors, neurotransmitter receptors and intracellular signaling molecules following repeated cocaine administration is altered in the mutant mice compared to that in wild-type mice. In the present study, we have investigated the role of Fos in regulating neuronal excitability at a cellular level and found that medium spiny nucleus accumbens neurons in the mutant mice exhibit increased excitability and attenuated inhibitory responses to stimulation of D1 receptors compared to those in wild-type mice. Our findings suggest that Fos functions in D1 receptor-bearing neurons to regulate neuronal activity which may contribute to the persistence of drug-induced changes.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / pharmacology
  • Action Potentials / drug effects
  • Action Potentials / genetics
  • Animals
  • Biophysics
  • Dopamine Agonists / pharmacology
  • Electric Stimulation
  • Female
  • Male
  • Mice
  • Mice, Mutant Strains
  • Neurons / cytology
  • Neurons / physiology*
  • Nucleus Accumbens / cytology*
  • Nucleus Accumbens / metabolism*
  • Oncogene Proteins v-fos / genetics
  • Oncogene Proteins v-fos / physiology*
  • Organ Culture Techniques
  • Patch-Clamp Techniques


  • Dopamine Agonists
  • Oncogene Proteins v-fos
  • 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine