Ryanodine receptor-2 upregulation and nicotine-mediated plasticity

EMBO J. 2011 Jan 5;30(1):194-204. doi: 10.1038/emboj.2010.279. Epub 2010 Nov 26.

Abstract

Nicotine, the major psychoactive component of cigarette smoke, modulates neuronal activity to produce Ca2+-dependent changes in gene transcription. However, the downstream targets that underlie the long-term effects of nicotine on neuronal function, and hence behaviour, remain to be elucidated. Here, we demonstrate that nicotine administration to mice upregulates levels of the type 2 ryanodine receptor (RyR2), a Ca2+-release channel present on the endoplasmic reticulum, in a number of brain areas associated with cognition and addiction, notably the cortex and ventral midbrain. Nicotine-mediated RyR2 upregulation was driven by CREB, and caused a long-lasting reinforcement of Ca2+ signalling via the process of Ca2+-induced Ca2+ release. RyR2 upregulation was itself required for long-term phosphorylation of CREB in a positive-feedback signalling loop. We further demonstrate that inhibition of RyR-activation in vivo abolishes sensitization to nicotine-induced habituated locomotion, a well-characterised model for onset of drug dependence. Our findings, therefore, indicate that gene-dependent reprogramming of Ca2+ signalling is involved in nicotine-induced behavioural changes.

MeSH terms

  • Animals
  • Calcium / metabolism
  • Calcium Signaling / drug effects
  • Cells, Cultured
  • Cerebellar Cortex / cytology
  • Cerebellar Cortex / drug effects
  • Cyclic AMP Response Element-Binding Protein / metabolism
  • Ganglionic Stimulants / administration & dosage
  • Ganglionic Stimulants / pharmacology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Motor Activity / drug effects
  • Nerve Net / drug effects
  • Nerve Net / metabolism
  • Neuronal Plasticity / drug effects*
  • Neurons / drug effects
  • Neurons / metabolism
  • Nicotine / administration & dosage
  • Nicotine / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Ryanodine Receptor Calcium Release Channel / genetics*
  • Ryanodine Receptor Calcium Release Channel / metabolism
  • Up-Regulation / drug effects*

Substances

  • Cyclic AMP Response Element-Binding Protein
  • Ganglionic Stimulants
  • Ryanodine Receptor Calcium Release Channel
  • Nicotine
  • Calcium