ZFIN ID: ZDB-PUB-150808-4
Neuronal Connectivity between Habenular Glutamate-Kisspeptin1 Co-expressing Neurons and the Raphe 5-HT System
Nathan, F.M., Ogawa, S., Parhar, I.S.
Date: 2015
Source: Journal of neurochemistry   135(4): 814-29 (Journal)
Registered Authors: Ogawa, Satoshi
Keywords: GPR54, Kiss1, serotonin, ventro-anterior MR, zebrafish
MeSH Terms:
  • Animals
  • Animals, Genetically Modified
  • Glutamate Decarboxylase/genetics
  • Glutamic Acid/metabolism*
  • Green Fluorescent Proteins/genetics
  • Green Fluorescent Proteins/metabolism
  • Habenula/cytology*
  • Habenula/metabolism
  • Kisspeptins/metabolism*
  • Male
  • Molecular Sequence Data
  • Nerve Net/metabolism
  • Neurons/metabolism*
  • RNA, Messenger/metabolism
  • Raphe Nuclei/cytology*
  • Raphe Nuclei/metabolism
  • Receptors, G-Protein-Coupled/metabolism
  • Serotonin/metabolism*
  • Transcription Factor Brn-3A/genetics
  • Transcription Factors/genetics
  • Transcription Factors/metabolism
  • Zebrafish
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 26250886 Full text @ J. Neurochem.
The habenula, located on the dorsal thalamic surface, is an emotional and reward processing center. As in the mammalian brain, the zebrafish habenula is divided into dorsal (dHb) and ventral (vHb) subdivisions that project to the interpeduncular nucleus (IPN) and median raphe (MR) respectively. Previously, we have shown that kisspeptin 1 (Kiss1) expressing in the vHb, regulates the serotonin (5-HT) system in the MR. However, the connectivity between the Kiss1 neurons and the 5-HT system remains unknown. To resolve this issue, we generated a specific antibody against zebrafish Kiss1 receptor (Kiss-R1); using this primary antibody we found intense immunohistochemical labeling in the ventro-anterior corner of the MR (vaMR) but not in 5-HT neurons, suggesting the potential involvement of interneurons in 5-HT modulation by Kiss1. Double-fluorescence labeling showed that the majority of habenular Kiss1 neurons are glutamatergic. In the MR region, Kiss1 fibers were mainly seen in close association with glutamatergic neurons and only scarcely within GABAergic and 5-HT neurons. Our findings indicate that the habenular Kiss1 neurons potentially modulate the 5-HT system primarily through glutamatergic neurotransmission via as yet uncharacterized interneurons. This article is protected by copyright. All rights reserved.