ZFIN ID: ZDB-PUB-080714-14
Multiple functions of GABA(A) and GABA(A) receptors during pattern processing in the zebrafish olfactory bulb
Tabor, R., Yaksi, E., and Friedrich, R.W.
Date: 2008
Source: The European journal of neuroscience   28(1): 117-127 (Journal)
Registered Authors: Friedrich, Rainer, Tabor, Rico, Yaksi, Emre
Keywords: GABA, neuronal circuit, olfactory bulb, pattern processing, zebrafish
MeSH Terms:
  • Animals
  • Baclofen/metabolism
  • Calcium/metabolism
  • Food
  • GABA Agonists/metabolism
  • GABA Antagonists/metabolism
  • Neural Pathways/anatomy & histology
  • Neural Pathways/physiology
  • Neurons/cytology
  • Neurons/metabolism
  • Odorants
  • Olfactory Bulb/cytology
  • Olfactory Bulb/metabolism*
  • Organophosphorus Compounds/metabolism
  • Patch-Clamp Techniques
  • Pyridazines/metabolism
  • Receptors, GABA-A/genetics
  • Receptors, GABA-A/metabolism*
  • Receptors, GABA-B/genetics
  • Receptors, GABA-B/metabolism*
  • Smell/physiology*
  • Zebrafish/anatomy & histology
  • Zebrafish/physiology
PubMed: 18616562 Full text @ Eur. J. Neurosci.
gamma-Aminobutyric acid (GABA)ergic synapses are thought to play pivotal roles in the processing of activity patterns in the olfactory bulb (OB), but their functions have been difficult to study during odor responses in the intact system. We pharmacologically manipulated GABA(A) and GABA(B) receptors in the OB of zebrafish and analysed the effects on odor responses of the output neurons, the mitral cells (MCs), by electrophysiological recordings and temporally deconvolved two-photon Ca(2+) imaging. The blockade of GABA(B) receptors enhanced presynaptic Ca(2+) influx into afferent axon terminals, and changed the amplitude and time course of a subset of MC responses, indicating that GABA(B) receptors have a modulatory influence on OB output activity. The blockade of GABA(A) receptors induced epileptiform firing, enhanced excitatory responses and abolished fast oscillations in the local field potential. Moreover, the topological reorganization and decorrelation of MC activity patterns during the initial phase of the response was perturbed. These results indicate that GABA(A) receptor-containing circuits participate in the balance of excitation and inhibition, the regulation of total OB output activity, the synchronization of odor-dependent neuronal ensembles, and the reorganization of odor-encoding activity patterns. GABA(A) and GABA(B) receptors are therefore differentially involved in multiple functions of neuronal circuits in the OB.