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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
10:16

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

Controversial issues in vertebrate olfactory transduction

G H Gold1

  • 1Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104-3308, USA.

Annual Review of Physiology
|April 1, 1999
PubMed

Insights

Cyclic adenosine monophosphate (cAMP) is the sole pathway for olfactory transduction, as evidenced by knockout mouse studies. New research explores odorant blocking phenomena and gating kinetics in olfactory signaling.

Area of Science:

  • Olfactory neuroscience
  • Molecular biology
  • Sensory transduction

Background:

  • Olfactory transduction mechanisms remain debated, with questions about multiple pathways.
  • The role of cyclic adenosine monophosphate (cAMP) as a second messenger is central to this debate.

Purpose of the Study:

  • To investigate the specific pathways involved in olfactory transduction.
  • To provide evidence supporting or refuting the role of cAMP as the sole second messenger.
  • To explore novel phenomena in olfactory signaling, such as odorant-induced blocking.

Main Methods:

  • Generation and analysis of knockout mice lacking specific components of the olfactory signaling pathway (cyclic nucleotide-gated channel and G(olf)).
  • Review of existing evidence regarding cAMP and gaseous second messenger pathways.
  • Examination of gating kinetics of cyclic nucleotide-gated channels and single-odorant molecule detection.

Main Results:

  • Results from both cyclic nucleotide-gated channel and G(olf) knockout mice strongly support cAMP as the exclusive second messenger in olfactory transduction.
  • Evidence for gaseous second messenger involvement was reviewed and found to be less conclusive.
  • Slow gating kinetics and single-odorant detection capabilities were discussed in the context of olfactory sensitivity.

Conclusions:

  • Cyclic adenosine monophosphate (cAMP) is confirmed as the sole second messenger mediating olfactory transduction.
  • The study addresses controversial issues by providing strong genetic evidence for a unified transduction pathway.
  • New olfactory phenomena, including odorant-induced response blocking, warrant further investigation.

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