Odorant-dependent generation of nitric oxide in Mammalian olfactory sensory neurons.
The gaseous signalling molecule nitric oxide (NO) is involved in various physiological processes including regulation of blood pressure, immunocytotoxicity and neurotransmission. In the mammalian olfactory bulb (OB), NO plays a role in the formation of olfactory memory evoked by pheromones as well as conventional odorants. While NO generated by the neuronal isoform of NO synthase (nNOS) regulates neurogenesis in the olfactory epithelium, NO has not been implicated in olfactory signal transduction. We now show the expression and function of the endothelial isoform of NO synthase (eNOS) in mature olfactory sensory neurons (OSNs) of adult mice. Using NO-sensitive micro electrodes, we show that stimulation liberates NO from isolated wild-type OSNs, but not from OSNs of eNOS deficient mice. Integrated electrophysiological recordings (electro-olfactograms or EOGs) from the olfactory epithelium of these mice show that NO plays a significant role in modulating adaptation. Evidence for the presence of eNOS in mature mammalian OSNs and its involvement in odorant adaptation implicates NO as an important new element involved in olfactory signal transduction. As a diffusible messenger, NO could also have additional functions related to cross adaptation, regeneration, and maintenance of MOE homeostasis.
Lehrstuhl für Zellphysiologie, Ruhr-Universität Bochum, Bochum, Germany.
Daniela
D
Brunert
Stefan
S
Kurtenbach
Sonnur
S
Isik
Heike
H
Benecke
Günter
G
Gisselmann
Wolfgang
W
Schuhmann
Hanns
H
Hatt
Christian H
CH
Wetzel
D000080462:Acyclic Monoterpenes; D000447:Aldehydes / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D004594:Electrophysiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D009830:Olfactory Bulb / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D011984:Sensory Receptor Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D013729:Terpenes / Q000494:pharmacology*
D000080462:Acyclic Monoterpenes; D000447:Aldehydes; D004791:Enzyme Inhibitors; D013729:Terpenes; D049452:Green Fluorescent Proteins; D005576:Colforsin; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; C007836:geraniol; D002118:Calcium; D019331:NG-Nitroarginine Methyl Ester; C031639:caprylic aldehyde