The locus coeruleus drives disinhibition in the midline thalamus via a dopaminergic mechanism

Nat Neurosci. 2018 Jul;21(7):963-973. doi: 10.1038/s41593-018-0167-4. Epub 2018 Jun 18.

Abstract

The paraventricular nucleus of the thalamus (PVT) is increasingly being recognized as a critical node linking stress detection to the emergence of adaptive behavioral responses to stress. However, despite growing evidence implicating the PVT in stress processing, the neural mechanisms by which stress impacts PVT neurocircuitry and promotes stressed states remain unknown. Here we show that stress exposure drives a rapid and persistent reduction of inhibitory transmission onto projection neurons of the posterior PVT (pPVT). This stress-induced disinhibition of the pPVT was associated with a locus coeruleus-mediated rise in the extracellular concentration of dopamine in the midline thalamus, required the function of dopamine D2 receptors on PVT neurons, and increased sensitivity to stress. Our findings define the locus coeruleus as an important modulator of PVT function: by controlling the inhibitory tone of the pPVT, it modulates the excitability of pPVT projection neurons and controls stress responsivity.

Publication types

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

MeSH terms

  • Animals
  • Dopamine / metabolism*
  • Electroshock
  • Fear / physiology
  • Female
  • Locus Coeruleus / metabolism*
  • Membrane Glycoproteins
  • Mice
  • Neural Inhibition / physiology*
  • Neural Pathways
  • Neurons / metabolism*
  • Receptors, Dopamine D2 / metabolism*
  • Receptors, Interleukin-1
  • Stress, Physiological / physiology*
  • Thalamus / metabolism*

Substances

  • Membrane Glycoproteins
  • Receptors, Dopamine D2
  • Receptors, Interleukin-1
  • TIRAP protein, human
  • Dopamine