Acute engagement of Gq-mediated signaling in the bed nucleus of the stria terminalis induces anxiety-like behavior

Mol Psychiatry. 2018 Jan;23(1):143-153. doi: 10.1038/mp.2016.218. Epub 2016 Dec 13.

Abstract

The bed nucleus of the stria terminalis (BNST) is a brain region important for regulating anxiety-related behavior in both humans and rodents. Here we used a chemogenetic strategy to investigate how engagement of G protein-coupled receptor (GPCR) signaling cascades in genetically defined GABAergic BNST neurons modulates anxiety-related behavior and downstream circuit function. We saw that stimulation of vesicular γ-aminobutyric acid (GABA) transporter (VGAT)-expressing BNST neurons using hM3Dq, but neither hM4Di nor rM3Ds designer receptors exclusively activated by a designer drug (DREADD), promotes anxiety-like behavior. Further, we identified that activation of hM3Dq receptors in BNST VGAT neurons can induce a long-term depression-like state of glutamatergic synaptic transmission, indicating DREADD-induced changes in synaptic plasticity. Further, we used DREADD-assisted metabolic mapping to profile brain-wide network activity following activation of Gq-mediated signaling in BNST VGAT neurons and saw increased activity within ventral midbrain structures, including the ventral tegmental area and hindbrain structures such as the locus coeruleus and parabrachial nucleus. These results highlight that Gq-mediated signaling in BNST VGAT neurons can drive downstream network activity that correlates with anxiety-like behavior and points to the importance of identifying endogenous GPCRs within genetically defined cell populations. We next used a microfluidics approach to profile the receptorome of single BNST VGAT neurons. This approach yielded multiple Gq-coupled receptors that are associated with anxiety-like behavior and several potential novel candidates for regulation of anxiety-like behavior. From this, we identified that stimulation of the Gq-coupled receptor 5-HT2CR in the BNST is sufficient to elevate anxiety-like behavior in an acoustic startle task. Together, these results provide a novel profile of receptors within genetically defined BNST VGAT neurons that may serve as therapeutic targets for regulating anxiety states and provide a blueprint for examining how G-protein-mediated signaling in a genetically defined cell type can be used to assess behavior and brain-wide circuit function.

Publication types

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

MeSH terms

  • Animals
  • Anti-Anxiety Agents / therapeutic use
  • Anxiety / drug therapy
  • Anxiety / genetics*
  • Anxiety / pathology*
  • Brain Mapping
  • Cannabinoid Receptor Antagonists / pharmacology
  • Clozapine / analogs & derivatives
  • Clozapine / pharmacology
  • Dark Adaptation / drug effects
  • Dark Adaptation / genetics
  • Disease Models, Animal
  • Estrenes / pharmacology
  • Excitatory Postsynaptic Potentials / drug effects
  • Excitatory Postsynaptic Potentials / genetics
  • Exploratory Behavior / drug effects
  • GTP-Binding Protein alpha Subunits, Gq-G11 / metabolism*
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • In Vitro Techniques
  • Male
  • Maze Learning / drug effects
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neurons / drug effects
  • Neurons / physiology*
  • Phosphodiesterase Inhibitors / pharmacology
  • Piperazines / pharmacology
  • Pyrrolidinones / pharmacology
  • RNA, Messenger / metabolism
  • Receptors, Drug / drug effects
  • Receptors, Drug / physiology
  • Rimonabant / pharmacology
  • Septal Nuclei / metabolism
  • Septal Nuclei / pathology*
  • Serotonin Receptor Agonists / pharmacology
  • Signal Transduction / drug effects
  • Signal Transduction / physiology*
  • Sodium Channel Blockers / pharmacology
  • Tetrodotoxin / therapeutic use
  • Vesicular Inhibitory Amino Acid Transport Proteins / genetics
  • Vesicular Inhibitory Amino Acid Transport Proteins / metabolism

Substances

  • Anti-Anxiety Agents
  • Cannabinoid Receptor Antagonists
  • Estrenes
  • Phosphodiesterase Inhibitors
  • Piperazines
  • Pyrrolidinones
  • RNA, Messenger
  • Receptors, Drug
  • Serotonin Receptor Agonists
  • Sodium Channel Blockers
  • Vesicular Inhibitory Amino Acid Transport Proteins
  • Viaat protein, mouse
  • 1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione
  • Green Fluorescent Proteins
  • Tetrodotoxin
  • GTP-Binding Protein alpha Subunits, Gq-G11
  • Clozapine
  • clozapine N-oxide
  • 1-(3-chlorophenyl)piperazine
  • Rimonabant