Elsevier

Neuroscience Letters

Volume 274, Issue 3, 29 October 1999, Pages 195-198
Neuroscience Letters

Cellular and subcellular localization of γ-aminobutyric acidB receptors in the rat olfactory bulb

https://doi.org/10.1016/S0304-3940(99)00697-7Get rights and content

Abstract

Olfactory nerve axons terminate in rounded regions of the olfactory bulb, termed glomeruli, where they make excitatory synapses with the dendrites of second-order neurons. Neurotransmission from the olfactory nerve to the postsynaptic targets is negatively regulated by γ-aminobutyric acid (GABA), and there is evidence that inhibition of sensory input is mediated, at least in part, by GABAB receptors. Using an antiserum that recognizes two GABAB receptor splice variants (GBR1a and GBR1b), we show here that GABAB receptors are located on the axon terminals of the olfactory nerve, where they are concentrated at sites of axodendritic apposition. Taken with previous data, these results indicate that GABAB receptors act presynaptically to regulate the release of glutamate from olfactory nerve terminals.

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Acknowledgements

We thank Dr. Jean-Marc Fritschy (University of Zürich) for his comments on the manuscript. This work was supported by the Italian M.U.R.S.T.

References (19)

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