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Perforated Patch-clamp Recording of Mouse Olfactory Sensory Neurons in Intact Neuroepithelium: Functional Analysis of Neurons Expressing an Identified Odorant Receptor
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Perforated Patch-clamp Recording of Mouse Olfactory Sensory Neurons in Intact Neuroepithelium: Functional Analysis of Neurons Expressing an Identified Odorant Receptor

Published on: July 13, 2015

Inhibitory odorant signaling in Mammalian olfactory receptor neurons

Kirill Ukhanov1, Elizabeth A Corey, Daniela Brunert

  • 1Whitney Laboratory, Center for Smell and Taste, University of Florida, Gainesville, FL 32610-0127, USA. ukhanov@mbi.ufl.edu

Journal of Neurophysiology
|December 25, 2009
PubMed

Insights

Phosphoinositide-3-kinase (PI3K) mediates inhibitory odorant signals in mammalian olfactory receptor neurons (ORNs). This PI3K-dependent signaling also contributes to mixture suppression in responses to natural odorants.

Area of Science:

  • Neuroscience
  • Olfactory Signaling
  • Molecular Biology

Background:

  • Olfactory receptor neurons (ORNs) exhibit both excitatory and inhibitory responses to odorants.
  • While excitatory pathways involving cyclic nucleotides are understood, the mechanisms of odorant-induced inhibition in ORNs remain unclear.
  • Phosphoinositide-3-kinase (PI3K) is a key signaling molecule in various cellular processes.

Purpose of the Study:

  • To investigate the role of PI3K in mediating inhibitory olfactory transduction in rodent ORNs.
  • To determine if PI3K activation by odorants affects the electrophysiological responses of ORNs.
  • To explore PI3K's contribution to odorant mixture suppression.

Main Methods:

  • Measurement of PI3K activation in olfactory cilia and epithelium in vitro upon odorant stimulation.
  • Identification of G-protein-coupled PI3K isoforms involved in olfactory transduction.
  • Electrophysiological recordings of ORN responses to assess modulation of magnitude and kinetics.

Main Results:

  • Odorants were shown to rapidly and transiently activate PI3K in rodent olfactory cilia and epithelium.
  • Specific G-protein-coupled PI3K isoforms were implicated in modulating ORN response magnitude and onset kinetics.
  • The inhibitory effect of one odorant on another was demonstrated to be PI3K-dependent.

Conclusions:

  • PI3K-dependent signaling pathways mediate inhibitory odorant input to mammalian ORNs.
  • PI3K plays a significant role in odorant mixture suppression observed in natural odorant responses.
  • This study provides compelling evidence for PI3K's involvement in the complexity of olfactory processing.

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