Prelimbic BDNF and TrkB signaling regulates consolidation of both appetitive and aversive emotional learning

Transl Psychiatry. 2012 Dec 18;2(12):e205. doi: 10.1038/tp.2012.128.

Abstract

The medial prefrontal cortex (mPFC) is known to regulate executive decisions and the expression of emotional memories. More specifically, the prelimbic cortex (PL) of the mPFC is implicated in driving emotional responses via downstream targets including the nucleus accumbens and amygdala, but mechanisms are yet to be fully understood. Therefore, we investigated whether prelimbic cortical brain-derived neurotrophic factor (BDNF) signaling through the high-affinity tyrosine kinase receptor B (TrkB) receptor may serve as a molecular mechanism underlying emotional memory encoding. Here, we utilized viral-mediated inducible bdnf deletion within the PL, as well as TrkB(F616A) mutant mice, wherein TrkB receptor point mutation results in its being highly sensitive to inhibition by small PP1-derivative molecules, serving as a specific TrkB inhibitor. The site-specific TrkB antagonism and viral-mediated bdnf deletion within the PL resulted in deficits in both cocaine-dependent associative learning and fear expression. Deficiencies were rescued by the novel TrkB agonist 7,8-dihydroxyflavone, indicating that PL BDNF expression and downstream signaling through the TrkB receptor are required for memory formation in both appetitive and aversive domains.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Appetitive Behavior / drug effects
  • Appetitive Behavior / physiology
  • Association Learning / drug effects
  • Association Learning / physiology*
  • Brain-Derived Neurotrophic Factor / genetics
  • Brain-Derived Neurotrophic Factor / metabolism*
  • Conditioning, Classical / drug effects
  • Conditioning, Classical / physiology
  • Flavones / pharmacology
  • Membrane Glycoproteins / drug effects
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Memory / physiology*
  • Mice
  • Mice, Knockout
  • Mice, Mutant Strains
  • Prefrontal Cortex / metabolism*
  • Protein-Tyrosine Kinases / drug effects
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Signal Transduction / drug effects
  • Signal Transduction / physiology

Substances

  • 6,7-dihydroxyflavone
  • Brain-Derived Neurotrophic Factor
  • Flavones
  • Membrane Glycoproteins
  • Ntrk2 protein, mouse
  • Protein-Tyrosine Kinases