Submit Data |  Help |  Video Tutorials |  News |  Publications |  FTP Download |  REST API |  Citing RGD |  Contact   

Dopamine D4 receptor excitation of lateral habenula neurons via multiple cellular mechanisms.

Authors: Good, Cameron H  Wang, Huikun  Chen, Yuan-Hao  Mejias-Aponte, Carlos A  Hoffman, Alexander F  Lupica, Carl R 
Citation: Good CH, etal., J Neurosci. 2013 Oct 23;33(43):16853-64. doi: 10.1523/JNEUROSCI.1844-13.2013.
Pubmed: (View Article at PubMed) PMID:24155292
DOI: Full-text: DOI:10.1523/JNEUROSCI.1844-13.2013

Glutamatergic lateral habenula (LHb) output communicates negative motivational valence to ventral tegmental area (VTA) dopamine (DA) neurons via activation of the rostromedial tegmental nucleus (RMTg). However, the LHb also receives a poorly understood DA input from the VTA, which we hypothesized constitutes an important feedback loop regulating DA responses to stimuli. Using whole-cell electrophysiology in rat brain slices, we find that DA initiates a depolarizing inward current (I(DAi)) and increases spontaneous firing in 32% of LHb neurons. I(DAi) was also observed upon application of amphetamine or the DA uptake blockers cocaine or GBR12935, indicating involvement of endogenous DA. I(DAi) was blocked by D4 receptor (D4R) antagonists (L745,870 or L741,742), and mimicked by a selective D4R agonist (A412997). I(DAi) was associated with increased whole-cell conductance and was blocked by Cs+ or a selective blocker of hyperpolarization-activated cyclic nucleotide-gated (HCN) ion channel, ZD7288. I(DAi) was also associated with a depolarizing shift in half-activation voltage for the hyperpolarization-activated cation current (Ih) mediated by HCN channels. Recordings from LHb neurons containing fluorescent retrograde tracers revealed that I(DAi) was observed only in cells projecting to the RMTg and not the VTA. In parallel with direct depolarization, DA also strongly increased synaptic glutamate release and reduced synaptic GABA release onto LHb cells. These results demonstrate that DA can excite glutamatergic LHb output to RMTg via multiple cellular mechanisms. Since the RMTg strongly inhibits midbrain DA neurons, activation of LHb output to RMTg by DA represents a negative feedback loop that may dampen DA neuron output following activation.

Annotation

Gene Ontology Annotations
Objects Annotated

Additional Information

 
CRRD Object Information
CRRD ID: 13702381
Created: 2018-07-18
Species: All species
Last Modified: 2018-07-18
Status: ACTIVE



NHLBI Logo

RGD is funded by grant HL64541 from the National Heart, Lung, and Blood Institute on behalf of the NIH.