Present address: Department of Neurobiology, Harvard Medical School, 220 Longwood Ave., Boston, MA 02215, USA.
Multiple functions of GABAA and GABAB receptors during pattern processing in the zebrafish olfactory bulb
Article first published online: 4 JUL 2008
© The Authors (2008). Journal Compilation © Federation of European Neuroscience Societies and Blackwell Publishing Ltd
European Journal of Neuroscience
Volume 28, Issue 1, pages 117–127, July 2008
How to Cite
Tabor, R., Yaksi, E. and Friedrich, R. W. (2008), Multiple functions of GABAA and GABAB receptors during pattern processing in the zebrafish olfactory bulb. European Journal of Neuroscience, 28: 117–127. doi: 10.1111/j.1460-9568.2008.06316.x
- Issue published online: 4 JUL 2008
- Article first published online: 4 JUL 2008
- Received 11 April 2008, revised 7 May 2008, accepted 8 May 2008
- neuronal circuit;
- olfactory bulb;
- pattern processing;
γ-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 GABAA and GABAB 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 Ca2+ imaging. The blockade of GABAB receptors enhanced presynaptic Ca2+ influx into afferent axon terminals, and changed the amplitude and time course of a subset of MC responses, indicating that GABAB receptors have a modulatory influence on OB output activity. The blockade of GABAA 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 GABAA 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. GABAA and GABAB receptors are therefore differentially involved in multiple functions of neuronal circuits in the OB.