[Ion channels and action potentials in olfactory receptor cells].
1Department of Physiology, School of Medicine, Fujita Health University, Toyoake, Japan. fkawai@fujita-hu.ac.jp
Nihon Shinkei Seishin Yakurigaku Zasshi = Japanese Journal of Psychopharmacology
|December 25, 2007
Summary
Olfactory receptor cells (ORCs) generate action potentials via somatic ionic channels, potentially contributing to odor adaptation. This review explores ORC spike generation and modulation by neurotransmitters and hormones.
Area of Science:
- Neuroscience
- Sensory Biology
- Molecular Biology
Context:
- Olfactory sensation begins with odorant binding to receptors on olfactory receptor cells (ORCs).
- This triggers a signaling cascade involving G-proteins, adenylyl cyclase, and cAMP.
- A cyclic nucleotide-gated channel opens, causing a depolarizing voltage change encoded into action potentials.
Purpose:
- To review the mechanisms of action potential generation in ORCs.
- To discuss the role of somatic ionic channels in ORC spike encoding and adaptation.
- To examine how neurotransmitters and hormones modulate ORC electrical activity.
Summary:
- Action potentials in ORCs are initiated by voltage-gated Na+ and T-type Ca2+ currents in the somatic membrane.
- While ciliary transduction is the primary adaptation mechanism, somatic channels may also contribute to spike encoding adaptation.
- Neurotransmitters and hormones can modulate these ionic currents and action potentials.
Impact:
- Provides a comprehensive overview of ORC electrophysiology.
- Highlights potential roles for somatic channels in olfactory adaptation.
- Offers insights into the complex regulation of olfactory signaling.
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