PUBLICATION

Early functional development of interneurons in the zebrafish olfactory bulb

Authors
Mack-Bucher, J.A., Li, J., and Friedrich, R.W.
ID
ZDB-PUB-070212-36
Date
2007
Source
The European journal of neuroscience   25(2): 460-470 (Journal)
Registered Authors
Friedrich, Rainer, Li, Jun
Keywords
none
MeSH Terms
  • Animals
  • Calcium/metabolism
  • Drug Interactions
  • ELAV Proteins/metabolism
  • ELAV-Like Protein 3
  • GABA Agonists/pharmacology
  • GABA Antagonists/pharmacology
  • Gene Expression Regulation, Developmental/physiology*
  • Green Fluorescent Proteins/metabolism
  • Homeodomain Proteins
  • Imaging, Three-Dimensional/methods
  • Interneurons/drug effects
  • Interneurons/physiology*
  • Muscimol/pharmacology
  • Neural Inhibition/drug effects
  • Odorants*
  • Olfactory Bulb*/cytology
  • Olfactory Bulb*/embryology
  • Olfactory Bulb*/growth & development
  • Pyridazines/pharmacology
  • Zebrafish/physiology*
  • Zebrafish Proteins/metabolism
  • gamma-Aminobutyric Acid/pharmacology
PubMed
17284187 Full text @ Eur. J. Neurosci.
Abstract
In the adult olfactory bulb (OB) of vertebrates, local GABAergic interneurons (INs) mediate recurrent and lateral inhibition between the principal neurons of the OB, the mitral cells (MCs), and play pivotal roles in the processing of odor-evoked activity patterns. The properties and functions of INs in the developing OB are, however, not well understood. We studied the functional development of INs in the OB of living zebrafish larvae 3-6 days postfertilization using anatomical techniques and in-vivo two-photon Ca(2+) imaging. We identified MCs and INs by cell-type-specific expression of transgenic fluorescent markers and found that the IN : MC ratio was lower than in the adult fish. Moreover, the fraction of INs responding with Ca(2+) signals to a set of natural odors was substantially lower than in adults. Odors of different chemical classes evoked overlapping patterns of Ca(2+) signals that were concentrated in the center of the IN layer. The GABA(A) receptor agonists GABA and muscimol strongly suppressed odor responses, whereas a GABA(A) receptor antagonist enhanced responses and altered the spatial distribution of odor-evoked activity. These results indicate that IN odor responses at early developmental stages are sparse and exhibit no obvious chemotopic organization. Nevertheless, GABAergic signaling is already inhibitory at early stages of OB development and strongly influences odor-evoked activity patterns. Hence, INs already participate in the processing of odor information at very early stages of OB development even though the majority of INs emerge only at later stages.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping